Increase In End-diastolic Volume Index Research Articles

Longitudinal changes in ventricular size and function are associated with death and transplantation late after the Fontan operation

BackgroundCross-sectional studies have reported that ventricular dilation and dysfunction are associated with adverse clinical outcome in Fontan patients; however, longitudinal changes and their relationship with outcome are not known.MethodsThis was a single-center retrospective analysis of Fontan patients with at least 2 cardiovascular magnetic resonance (CMR) scans without intervening interventions. Serial measures of end-diastolic volume index (EDVI), end-systolic volume index (ESVI), ejection fraction (EF), indexed mass (massi), mass-to-volume ratio, and end-systolic wall stress (ESWS) were used to estimate within-patient change over time. Changes were compared for those with and without a composite outcome (death, heart transplant, or transplant listing) as well as between patients with left (LV) and right ventricular (RV) dominance.ResultsData from 156 patients were analyzed with a mean age at 1st CMR of 17.8 ± 9.6 years. 490 CMRs were included with median of 3 CMRs/patient (range 2–9). On regression analysis with mixed effects models, volumes and ESWS increased, while mass, mass-to-volume ratio, and EF decreased over time. With a median follow-up of 10.2 years, 14% met the composite outcome. Those with the composite outcome had a greater increase in EDVI compared to those without (4.7 vs. 0.8 ml/BSA1.3/year). Compared with LV dominance, RV dominance was associated with a greater increase in ESVI (1.4 vs. 0.5 ml/BSA1.3/year), a greater decrease in EF (− 0.61%/year vs. − 0.24%/year), and a higher rate of the composite outcome (21% vs. 8%).ConclusionsVentricles in the Fontan circulation exhibit a steady decline in performance with an increase in EDVI, ESVI, and ESWS, and decrease in EF, mass index, and mass-to-volume ratio. Those with death or need for heart transplantation have a faster increase in EDVI. Patients with rapid increase in EDVI (> 5 ml/BSA1.3/year) may be at a higher risk of adverse outcomes and may benefit from closer surveillance. RV dominance is associated with worse clinical outcomes and remodeling compared to LV dominance.

Abstract 12145: Cardiac Magnetic Resonance Late Gadolinium Enhancement is Associated With Ventricular Elastance That May Predict Latent Ventricular Dysfunction After Fontan Procedure

Backgrounds: Systemic right ventricular circulation after Fontan procedures is known to have late hemodynamic complications. Although a number of studies have investigated the factors that may impact on survival, postoperative outcomes after palliations remain to be elucidated. Objective: The purpose of this study is to investigate the prognostic value of myocardial fibrosis identified by cardiac magnetic resonance imaging (cMRI) in patients with single ventricular physiology. Methods: Consecutive 23 patients undergoing Fontan procedures were prospectively scheduled to have cMRI study with late gadolinium enhancement (LGE) imaging and ventricle circumferential strain measurement before and 4 months after Fontan operation. Results: Of 23 patients (mean age 3.3±0.9 years), 7 were positive for LGE (LGE+) and median percent LGE was 3.0% (interquartile range 3.0% to 7.5%). Pre-Fontan examinations revealed that patients with LGE+ showed an increase in end-diastolic volume index (139.7±26.8 ml/BSA vs. 113.3±20.9 ml/BSA; P=0.02) and end-systolic volume index (ESVI: 99.9±32.2 ml/BSA vs. 70.8±20.0 ml/BSA; P=0.01) compared with those without LGE (LGE-). In contrast to LGE- group, LGE+ patients showed lower global circumferential strain (4.1±2.3% vs. 7.9±2.7%, P=0.006), decreased ejection fraction (EF: 29±9.1% vs. 38±8.7%; P=0.04), and reduced end-systolic elastance (1.1±0.3 mm Hg/ml/m2 vs. 1.7±0.5 mm Hg/ml/m2). In addition, LGE+ group had higher levels of BNP (91.0±72.4 pg/ml vs. 30.9±44.0 pg/ml, P=0.02) and New York University Pediatric Heart Failure Index (10.9±3.3 vs. 7.8±1.1, P=0.02) than LGE- group. This was validated by positive correlations between the area of LGE versus ESVI (r=0.85, P=0.01) and BNP levels (r=0.82, P=0.02), respectively. At 4 months after Fontan procedure, LGE- group showed higher EF (37.5±8.6% vs. 24.0±8.9%, P=0.02) compared with those in LGE+ patients, and increased global circumferential strain (6.5±2.0% to 7.4±2.7%, P=0.04). Conclusion: LGE identified by cMRI before operation may be associated with lower ventricular elastance that resulted in poorer functional recovery after staged palliation. This novel strategy may provide a prognostic value of latent myocardial dysfunction after Fontan procedure.

Abstract 17083: Assessment of Both Coronary Microvascular Damage and Left Ventricular Chamber Stiffness after Successful Percutaneous Coronary Intervention Predicts In-Hospital Cardiac Complications and Left Ventricular Remodeling in ST-Segment Elevation Myocardial Infarction

Background: In ST-segment elevation myocardial infarction (STEMI), the short deceleration time of left ventricular (LV) early filling by Doppler is a powerful independent predictor of clinical cardiac events. It has also been reported that the coronary flow velocity pattern in patients with microvascular obstruction is characterized by the presence of early systolic retrograde flow and a rapid diastolic deceleration time (DDT). The purpose of this study was to examine the effects of both microvascular damage and LV chamber stiffness on cardiac complications and LV remodeling after successful percutaneous coronary intervention (PCI) in STEMI patients. Methods: Two hundred and one consecutive patients with first anterior STEMI were studied following successful PCI. Microvascular damage was evaluated on the basis of coronary flow velocity patterns using Doppler guidewires. We defined the presence of microvascular obstruction as DDT ≤600 ms and the presence of systolic flow reversal. LV filling patterns were determined by LV inflow pulsed-wave Doppler examination on day 3 after STEMI. Deceleration time ≤130 ms was defined as restrictive. We classified patients into three categories: without restrictive and microvascular obstruction (group 1, n=116), with restrictive or microvascular obstruction (group 2, n= 38), and with restrictive and microvascular obstruction (group 3, n=47). Left ventriculograms were obtained immediately and 6 months after PCI. LV remodeling was defined as an increase in end-diastolic volume index ≥20%. The clinical event rate was compared among the 3 groups. Results: The in-hospital event rates for LV thrombus (2/116 [2%], 5/38 [13%] and 14/47 [30%], respectively; P < 0.01) and congestive heart failure (5/116 [4%], 10/38 [26%], and 22/47 [47%]; P < 0.01) were highest in group 3 and lowest in group 1. Group 3 was at the highest risk of LV remodeling, while group 1 was at the lowest (7/116 [6%], 14/38 [37%], and 39/47 [83%]; P < 0.01). Conclusions: Assessment of both microvascular damage and LV chamber stiffness can accurately predict in-hospital complications and LV remodeling in STEMI patients who underwent successful reperfusion of the infarct-related coronary artery, identifying a subset of high risk patients.

Impact of transmural necrosis on left ventricular remodeling and clinical outcomes in patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction

We sought to determine which contrast-enhanced magnetic resonance imaging (CE-MRI) parameter is the best predictor for left ventricular (LV) remodeling and clinical outcomes after ST-segment elevation myocardial infarction (STEMI). In 135 patients undergoing primary percutaneous coronary intervention (PCI) for STEMI, CE-MRI was performed at a median of 7 days after PCI. Echocardiography was performed soon after PCI and at a follow-up visit. LV remodeling was defined as an increase in end-diastolic volume index ≥20 % on follow-up echocardiography. Several CE-MRI parameters such as infarct size, transmurality, microvascular obstruction (MVO), and hemorrhagic infarction were tested using a 17-myocardial segment model. Optimal cut-off values were derived from receiver-operating characteristic curve (ROC) analysis. Twenty-eight patients (21 %) demonstrated LV remodeling. Although the addition of transmural necrotic segment count, infarct size, and MVO segment count to clinical models improved the prediction of LV remodeling in multivariable regression analysis, transmural necrotic segment count had better incremental predictive value than other CE-MRI parameters. The aggregate consideration of infarct size (cut-off ≥25 %), transmural necrotic segment count (≥5), and MVO segment count (≥2) yielded better diagnostic performance than each of the individual parameters in ROC analysis (P < 0.01). In Kaplan-Meier curve analysis, patients with transmural necrotic segment counts ≥5 had a higher incidence of major adverse cardiac event than did those without. The transmural necrotic segment count is the most important predictor of LV remodeling and clinical outcomes. The combination of CE-MRI parameters including infarct size, transmural necrotic segment count, and MVO segment count appeared to increase reliability for predicting LV remodeling.

AS-022: Impact of Transmural Necrosis on Left Ventricular Remodeling and Clinical Outcomes in Patients Undergoing Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction

We sought to determine which contrast-enhanced magnetic resonance imaging (CE-MRI) parameter is the best predictor for left ventricular (LV) remodeling and clinical outcomes after ST-segment elevation myocardial infarction (STEMI). In 135 patients undergoing primary percutaneous coronary intervention (PCI) for STEMI, CE-MRI was performed at a median of 7 days after PCI. Echocardiography was performed soon after PCI and at a follow-up visit. LV remodeling was defined as an increase in end-diastolic volume index ≥20 % on follow-up echocardiography. Several CE-MRI parameters such as infarct size, transmurality, microvascular obstruction (MVO), and hemorrhagic infarction were tested using a 17-myocardial segment model. Optimal cut-off values were derived from receiver-operating characteristic curve (ROC) analysis. Twenty-eight patients (21 %) demonstrated LV remodeling. Although the addition of transmural necrotic segment count, infarct size, and MVO segment count to clinical models improved the prediction of LV remodeling in multivariable regression analysis, transmural necrotic segment count had better incremental predictive value than other CE-MRI parameters. The aggregate consideration of infarct size (cut-off ≥25 %), transmural necrotic segment count (≥5), and MVO segment count (≥2) yielded better diagnostic performance than each of the individual parameters in ROC analysis (P < 0.01). In Kaplan–Meier curve analysis, patients with transmural necrotic segment counts ≥5 had a higher incidence of major adverse cardiac event than did those without. The transmural necrotic segment count is the most important predictor of LV remodeling and clinical outcomes. The combination of CE-MRI parameters including infarct size, transmural necrotic segment count, and MVO segment count appeared to increase reliability for predicting LV remodeling.

Apical myectomy: A new surgical technique for management of severely symptomatic patients with apical hypertrophic cardiomyopathy

Apical hypertrophic cardiomyopathy is a morphologic variant in which the hypertrophy is primarily localized to the apex of the left ventricle. A subset of patients have progressive, drug-refractory diastolic heart failure with severely limiting symptoms caused by low cardiac output. Heart transplantation has been the only therapeutic option available for such patients. This study analyzes clinical and hemodynamic outcomes of a novel surgical technique to improve diastolic filling by means of left ventricular cavity enlargement. Forty-four symptomatic patients underwent apical myectomy to augment left ventricular end-diastolic volume. Myectomy was performed through an apical incision, and hypertrophic muscle was excised at the apex and midventricle. Information from a prospective database was supplemented by surveys, patient contact, and medical records. The mean age of the patients was 50 +/- 17 years, and 66% were women. All patients were severely limited with dyspnea, 61% had angina, and 59% had syncope/presyncope. Ninety-one percent of patients were in New York Heart Association class III or IV. A mean of 16 +/- 7 g of muscle was removed. Preoperative and postoperative hemodynamic catheterization (n = 14) showed a decrease in left ventricular end-diastolic pressure from 28 +/- 9 to 24 +/- 7 mm Hg (P = .002) and an increase in end-diastolic volume index from 55 +/- 17 to 68 +/- 18 mL/m(2) (P = .003). Invasive measurements of stroke volume increased from 56 +/- 17 to 63 +/- 19 mL (P = .007). Of the 42 patients who survived to hospital discharge, 41 had improvement in symptoms. Mean peak maximum oxygen consumption with exercise (n = 5) increased from 13.5 +/- 4.4 to 15.8 +/- 4.6 mL/kg per minute. Survival at 1, 3, and 5 years was 95%, 81%, and 81%, respectively. At follow-up of 2.6 +/- 3.1 years, 23 (74%) patients were in New York Heart Association class I or II. One patient underwent heart transplantation 5 years after apical myectomy. Apical myectomy improves functional status by decreasing left ventricular end-diastolic pressure, improving operative compliance, and increasing stroke volume. This procedure might be of value in other patients with hypertrophic cardiomyopathy who have severe hypertrophy and small left ventricular end-diastolic volume.

Balloon sizing in surgical ventricular restoration: What volume are we targeting?

Surgical ventricular restoration (SVR) by endoventricular circular patch plasty was described by Dor and colleagues as a new approach to treat patients with left ventricular (LV) aneurysm. Over time, this technique was optimized, and most centers currently use an intraventricular balloon to standardize volume and shape of the residual cavity. During SVR, the left ventricle is opened through the infarct, and an endocardial encircling suture (Fontan stitch) is placed at the transitional zone between scarred and normal tissue. Next, the balloon is introduced into the left ventricle and filled with 50 to 60 mL saline per square meter of body-surface area. The Fontan stitch is tightened to approximate the ventricular wall to the balloon, and the residual orifice is closed with a patch. Subsequently, the excluded scar tissue is closed over the patch to ensure hemostasis. The guiding principle behind this operation is the concept that SVR reduces wall stress (according to Laplace’s law) leading to reduced oxygen demand and improved function of the healthy remote myocardium. The balloon technique is generally considered to produce more consistent and more predictable results with improved clinical outcome. One of the first papers to describe balloon sizing mentioned that the balloon was inflated to check that the new LV diastolic volume was between 50 and 70 mL/m. Recently, Dor and associates reported a tighter range of 50 to 60 mL/m and explained that the balloon should help to avoid excessive volume reduction, which might cause impaired diastolic function and restrictive cardiomyopathy. The technique is referred to as ‘‘diastolic volume balloon sizing,’’ but the basis for selecting this specific target volume range was not explicitly mentioned. To put the values in perspective, recent magnetic resonance imaging studies indicate a normal end-diastolic volume index (EDVI) of 74 15 mL/m in men and 65 11 mL/m in women with, respectively, 25 9 mL/m and 18 5 mL/m for indexed end-systolic volume (ESVI). Furthermore, a 20% increase in EDVI after myocardial infarction is considered to indicate remodeling, and an ESVI>60 mL/m is associated with advanced

Abstract 4206: Microvascular Dysfunction and Left Ventricular Chamber Stiffness after Successful Percutaneous Coronary Intervention Critically Determine Left Ventricular Remodeling in Patients with Acute Myocardial Infarction

In patients with acute myocardial infarction (AMI), the short deceleration time of left ventricular (LV) early filling by Doppler is a powerful independent predictor of LV remodeling. On the other hand, recent studies have shown that microvascular dysfunction in recanalized infarct-related coronary arteries may predict progressive LV dilation. The purpose of this study was to examine the effects of both microvascular dysfunction and LV chamber stiffness on LV remodeling after successful percutaneous coronary intervention (PCI) in AMI patients. Two hundred and one consecutive patients with first anterior AMI were studied following successful PCI. Microvascular injury was evaluated on the basis of coronary flow velocity patterns immediately after successful PCI using Doppler guidewires. We defined the presence of microvascular dysfunction as diastolic deceleration time ≤600 ms and the presence of systolic flow reversal. LV filling patterns were determined by mitral inflow pulsed-wave Doppler examination on day 3 after AMI. Deceleration time ≤130 ms was defined as restrictive. We classified the patients into three categories: without restrictive and microvascular dysfunction (group 1, n=116), with restrictive or microvascular dysfunction (group 2, n= 38), and with restrictive and microvascular dysfunction (group 3, n=47). Left ventriculograms were obtained immediately and 6 months after PCI. LV remodeling was defined as an increase in end-diastolic volume index ≥20%. Group 3 was at the highest risk of LV remodeling, while group 1 was at the lowest (Table ). Assessment of both microvascular dysfunction and LV chamber stiffness enable accurate prediction of LV remodeling in AMI patients after successful PCI. LV remodeling in each group

Infarct size by contrast enhanced cardiac magnetic resonance is a stronger predictor of outcomes than left ventricular ejection fraction or end-systolic volume index: prospective cohort study

Objectives:Ejection fraction (EF) and end-systolic volume index (ESVI) are established predictors of outcomes following ST-segment elevation myocardial infarction (STEMI). We sought to assess the relative impact of infarct size, EF...

Abstract 3340: Coronary Flow Velocity Pattern Immediately After Percutaneous Coronary Intervention Predicts Left Ventricular Remodeling in Patients with Acute Myocardial Infarction

Background: Studies using the Doppler guidewire have shown that coronary flow velocity (CFV) pattern in recanalized infracted arteries predicts recovery of regional left ventricular (LV) function, in-hospital complications, and long-term cardiac events. However, the relationship between the CFV pattern after reperfusion and serial changes in LV volumes is not clear. We postulated that the quantitative CFV measurement immediately after successful percutaneous coronary intervention (PCI) might be associated with the LV remodeling. To test this hypothesis, we prospectively analyzed the LV remodeling according to CFV parameters measured by the Doppler guidewire in patients with acute myocardial infarction (AMI). Methods: Consecutive 211 patients with first-time anterior AMI underwent successful PCI (&lt;50% residual stenosis with TIMI flow grade 2–3) and coronary flow measurement with the Doppler guidewire. The CFV spectrum provided the following parameters: time-averaged peak velocity (cm/s), systolic peak velocity (cm/s), and diastolic deceleration time (ms). Left ventriculograms obtained immediately after PCI and 6 months after the infarction were analyzed to measure the end-diastolic volume index and end-systolic volume index. The LV remodeling was defined as an increase in end-diastolic volume index ≥20%. Result: The optimal cutoff values to predict LV remodeling (defined as 6-month LV dilation ≥20%) were 20 cm/s for time-averaged peak velocity, 0 cm/s for systolic peak velocity and 550 ms for diastolic deceleration time (sensitivity=0.63, specificity=0.56; sensitivity=0.76, specificity=0.85; and sensitivity=0.85, specificity=0.85, respectively). Systolic peak velocity and diastolic deceleration time correlated to the LV end-diastolic volume index obtained 6 months after AMI(r= −0.67; p&lt;0.001 and r= −0.78; p&lt;0.001, respectively). Conclusions: The CFV pattern appears to be an accurate predictor of LV remodeling even in patients who received successful PCI in the left anterior descending coronary artery immediately after AMI. This index, therefore, identifies a subset of patients at-risk.

Comparison of the usefulness of Doppler-derived deceleration time versus plasma brain natriuretic peptide to predict left ventricular remodeling after mechanical revascularization in patients with ST-elevation acute myocardial infarction and left ventricular systolic dysfunction

The correlation between Doppler deceleration time (DT) and brain natriuretic peptide (BNP) and their predictive value for detecting left ventricular (LV) remodeling in patients who are treated with primary percutaneous intervention for infarction and LV dysfunction are unknown. Fifty-six patients (64 +/- 12 years of age; 11 women) who had a first ST-segment elevation myocardial infarction and systolic dysfunction that was successfully treated with direct primary coronary intervention underwent 2-dimensional Doppler echocardiographic and plasma BNP evaluation at days 1 and 3 and 1 and 6 months after the index infarction. Repeat coronary angiograms were obtained at 1 and 6 months. Because of previous consistent evidence, 3 days after the index infarction was the time point of comparison between BNP and DT values. Echocardiographic LV remodeling was defined as an increase in end-diastolic volume index above baseline values of 2 x SD. Ventricular remodeling occurred in 20 patients (36%). Multivariate analyses that included BNP level, Doppler DT, echocardiographic measurements of systolic function, peak creatine kinase, and anterior infarct location showed Doppler DT to be the only predictor of LV remodeling (odds ratio 0.963, 95% confidence interval 0.936 to 0.990, p = 0.008). The optimal cutoff for DT in the prediction of 6-month LV remodeling was <136 ms (sensitivity 75%, specificity 97%, accuracy 81%, area under receiver-operating characteristic curve 0.90). Thus, in patients who have a first ST-segment elevation myocardial infarction and LV systolic dysfunction that is successfully treated with primary percutaneous coronary intervention, Doppler-derived DT 3 days after index infarction is more effective than BNP level in detecting patients who are at higher risk for 6-month LV remodeling.

Heterogeneity of left ventricular remodeling after acute myocardial infarction: Results of the Gruppo Italiano per lo Studio della Sopravvivenza nell’Infarto Miocardico-3 Echo Substudy

Background Left ventricular (LV) remodeling after acute myocardial infarction has still to be clarified in the thrombolytic era. Methods To evaluate timing and the magnitude and pattern of postinfarct LV remodeling, a subset of 614 patients enrolled in the Gruppo Italiano per lo Studio della Sopravvivenza nell’Infarto Miocardico-3 Echo Substudy underwent serial 2-dimensional echocardiograms at 24 to 48 hours from symptom onset (S1), at hospital discharge (S2), at 6 weeks (S3), and at 6 months (S4) after acute myocardial infarction. Results During the study period the end-diastolic volume index (EDVi) increased (P <.001) and wall motion abnormalities (%WMA) decreased (P <.001), whereas ejection fraction (EF) remained unchanged. Nineteen percent of patients showed a > 20% increase in EDVi at S2 compared with S1 (severe early dilation), and 16% of patients showed a > 20% dilation at S4 compared with S2 (severe late dilation). Independent predictors of severe in-hospital LV dilation were relatively small EDVi (odds ratio [OR] 0.961, 95% confidence interval [CI] 0.947-0.974, P =.0001) and relatively large %WMA (OR 1.030, 95% CI 1.013-1.048, P =.0005). Similarly, smaller predischarge EDVi (OR 0.975, 95% CI 0.963-0.987, P =.0001), greater %WMA (OR 1.026, 95% CI 1.008-1.045, P =.0042), and moderate to severe mitral regurgitation (OR 2.261, 95% CI 1.031-4.958, P = 0.0417) independently predicted severe late dilation. Importantly, 92% of the patients with severe early dilation did not have further dilation at S4, and 91% of patients with severe late dilation did not have in-hospital dilation. EF was unchanged over time in patients with early dilation, whereas it significantly decreased in those with late dilation. Conclusions Although in-hospital LV enlargement is not predictive of subsequent dilation and dysfunction, late remodeling is associated with progressive deterioration of global ventricular function over time: patients with extensive %WMA and not significantly enlarged ventricular volume before discharge are at higher risk for progressive dilation and dysfunction. (Am Heart J 2001;141:131-8.)

Long-term effects of bisoprolol compared with imidapril on left ventricular remodeling after reperfusion in acute myocardial infarction: An angiographic study in patients with maintained vessel patency

Background Although angiotensin-converting enzyme inhibitor attenuates ventricular enlargement, whether β-blocker therapy induces regression of left ventricular remodeling is not known. The purpose of this study was to compare the effects of bisoprolol therapy with those of imidapril therapy on left ventricular remodeling after acute myocardial infarction (AMI). Methods Sixty patients with AMI who underwent reperfusion therapy were randomly assigned to an imidapril group (20 patients), a bisoprolol group (20 patients), or a control group (20 patients). Administration was started within 24 hours. Left ventricular function on admission and 3 months and 1 year after AMI was investigated. Results Baseline characteristics on admission were similar in the 3 groups except for sex distribution. Mean pulmonary capillary wedge pressure and left ventricular end-diastolic pressure in the bisoprolol group were higher than those in the imidapril group 1 year after admission (pulmonary capillary wedge pressure: 12 ± 7 vs 8 ± 2 mm Hg, left ventricular end-diastolic pressure: 17 ± 8 vs 11 ± 4 mm Hg, P <.01). Left ventricular end-diastolic volume index (EDVI) increased in the bisoprolol group throughout the 1-year period (P <.01), whereas EDVI in the imidapril group decreased (P <.01). The increases in EDVI during 1 year in the bisoprolol group were greater than those of the other 2 groups (bisoprolol: 12 ± 10, imidapril: –9 ± 7, control: 4 ± 11 mL/m2, P <.01). Conclusions Early treatment with bisoprolol in AMI cannot prevent left ventricular remodeling, whereas imidapril attenuates left ventricular dilation by decreasing preload. (Am Heart J 2000;140:e27.)

Long-term implications of reocclusion on left ventricular size and function after successful thrombolysis for first anterior myocardial infarction.

Successful thrombolysis can prevent left ventricular dilatation after acute myocardial infarction. However, in almost 30% of patients, reocclusion occurs. The aim of this study was to assess the long-term implications of reocclusion on left ventricular size and function. Fifty-six patients were studied with two-dimensional echocardiography at baseline (2 +/- 1.6 days) and 5.0 +/- 1.4 years after first anterior myocardial infarction. All patients (a subset of those enrolled in the APRICOT trial) had a patent infarct-related artery when studied < 48 hours after thrombolysis and underwent repeat coronary angiography at 3 months. Baseline characteristics were comparable in patients with (n = 17) and without reocclusion (n = 39). Left ventricular volume indexes were stable in patients without reocclusion. Patients with reocclusion, however, showed a significant increase in end-diastolic volume index (EDVI; P = .008) and end-systolic volume index (ESVI; P = .039). Furthermore, patients without reocclusion demonstrated improvement in wall motion score index (WMSI; P = .0001) and ejection fraction (EF; P = .016), whereas patients with reocclusion did not. After 5 years, patients with reocclusion had significantly larger volume indexes (EDVI, 99 +/- 41 versus 76 +/- 22 mL/m2, P = .007; ESVI, 59 +/- 40 versus 39 +/- 20 mL/m2, P = .017) and more compromised left ventricular function (WMSI, 1.63 +/- 0.33 versus 1.39 +/- 0.32, P = .013; EF, 45 +/- 13% versus 51 +/- 11%, P = .077) than patients without reocclusion. Multivariate analysis identified baseline WMSI and reocclusion as significant independent predictors of left ventricular dilatation. Reocclusion of the infarct-related artery within 3 months of successful thrombolysis is associated with left ventricular dilatation and is detrimental to functional recovery of left ventricular function 5 years after first anterior myocardial infarction.

Left ventricular wall motion score as an early predictor of left ventricular dilation and mortality after first anterior infarction treated with thrombolysis

To recognize patients prone to subsequent left ventricular dilation after the acute phase of a myocardial infarction treated with thrombolysis, we studied 233 patients with a first anterior infarction, treated with thrombolysis, with 2-dimensional echocardiography within 12 hours after admission and 3 months later. A wall motion score index (WMSI) and left ventricular volumes were assessed, and enzymatic infarct size was expressed as cumulative alphahydroxybutyrate dehydrogenase determined in the first 72 hours after infarction. Patients who died (17 of 233, 7%) after a mean follow-up of 517 days had a significantly higher acute WMSI (2.1 ± 0.3, mean ± SD) than those who survived (1.9 ± 0.4) (p = 0.006). With use of this cutoff value of 2 for WMSI, ventricles with an acute WMSI ≤2 (62%) showed no increase in end-diastolic volume index (EDVI) or end-systolic volume index (ESVI), whereas ventricles with an acute WMSI >2 (38%) showed a significant increase in ESVI (6.1 ± 12.2 ml/m 2) and in EDVI (10.3 ± 16.6 ml/m 2) in the first 3 months. Using a cutoff value of 1,000 U/L for cumulative alphahydroxybutyrate dehydrogenase, only infarcts with a value of > 1,000 U/L (52%) caused a significant increase in EDVI (10.8 ± 14.3 ml/m 2) and ESVI (6.5 ± 10.0 ml/m 2) in the first 3 months. Thus, acutely assessed WMSI of >2 can readily predict subsequent dilation in patients with a first anterior infarction treated with streptokinase and is a good predictor of mortality. Enzymatic infarct size also is a good predictor of dilation, although not available until 3 days after infarction.

Impact of age on the cardiovascular response to dynamic upright exercise in healthy men and women

To examine whether age differentially modifies the physiological response to exercise in men and women, we performed gated radionuclide ventriculography with measurement of left ventricular volumes at rest and during peak upright cycle exercise in 200 rigorously screened healthy sedentary volunteers (121 men and 79 women) aged 22-86 yr from the Baltimore Longitudinal Study of Aging. At rest in the sitting position, age-associated declines in heart rate (HR) and increases in systolic blood pressure occurred in both sexes. Whereas resting cardiac index (CI) and total systemic vascular resistance (TSVR) in men did not vary with age, in women resting CI decreased 16% and TSVR increased 46% over the six-decade age span. Men, but not women, demonstrated an age-associated increase of approximately 20% in sitting end-diastolic volume index (EDVI), end-systolic volume index (ESVI), and stroke volume index over this age span. Peak cycle work rate declined with age approximately 40% in both sexes, but at any age it was greater in men than in women even after normalization for body weight. At peak effort, ejection fraction (EF), HR, and CI were reduced similarly with age while ESVI and TSVR were increased in both sexes; EDVI increased 35% with age and stroke work index (SWI) rose 19% in men, but neither was related to age in women; and stroke volume index did not vary with age in either sex. When hemodynamics were expressed as the change from rest to peak effort as an index of cardiovascular reserve function, both sexes demonstrated age-associated increases in EDVI and ESVI and reductions in EF, HR, and CI. However, the exercise-induced reduction in ESVI and the increases in EF, CI, and SWI from rest were greater in men than in women. Thus, age and gender each have a significant impact on the cardiac response to exhaustive upright cycle exercise.

Effects of acute beta-adrenergic receptor blockade on age-associated changes in cardiovascular performance during dynamic exercise.

The cardiovascular response to beta-adrenergic stimulation is markedly blunted with advancing age, and this blunting may underlie some of the prominent age-associated changes in the hemodynamic profile during dynamic exercise. To examine this hypothesis, we administered the nonselective beta-adrenergic receptor blocker propranolol (0.15 mg/kg IV) to 25 healthy normotensive men ages 28 to 72 years from the Baltimore Longitudinal Study of Aging (BLSA) immediately before maximal upright cycle ergometry with 99mTc gated cardiac blood pool scintigraphy. Their hemodynamic responses to exercise were compared with those of 70 age-matched healthy unmedicated male BLSA control subjects. The maximal cycle work rate achieved was similar in propranolol-treated men (158 +/- 32 W) and control subjects (148 +/- 32 W) and declined similarly with age in both groups. Hemodynamics at seated rest were not age-related in either group; however, propranolol-treated men had lower heart rates (HR), systolic blood pressure (SBP), ejection fraction, and cardiac index than control subjects but higher end-diastolic volume index (EDVI) and end-systolic volume index (ESVI) by covariance analysis. At maximal effort, several striking age-drug interactions were evident: Propranolol caused a greater reduction in HR and greater increases in EDVI and stroke volume index (SVI) in younger than in older men. Hence, at maximal work rate, HR declined less with age in the propranolol group (0.46 versus 1.09 beats per minute per year, P < .05 by covariance analysis); EDVI and SVI decreased with age (0.27 and 0.48 mL/m2 per year, respectively) after propranolol compared with increases of 0.47 and 0.16 mL/m2 per year in control subjects, respectively, each P < or = .05 by covariance analysis. The left ventricular contractility index, SBP/ESVI, at exhaustion was reduced by propranolol to a greater extent in younger than older men. Thus, acute beta-adrenergic blockade reverses the age-associated ventricular dilation at end diastole and end systole observed during upright cycle exercise and blunts the decline in maximal HR and myocardial contractility. These data suggest that the age-associated declines in maximal HR and left ventricular contractility during vigorous exercise are manifestations of reduced beta-adrenergic responsivity with advancing age which is partially offset by exercise-induced ventricular dilation.

Late potentials and ventricular enlargement after myocardial infarction. A new role for high-resolution electrocardiography?

Arrhythmias are common in patients who have developed ventricular enlargement after myocardial infarction. A prospective study was undertaken to assess the relation between ventricular dilatation and the development of late potentials after myocardial infarction. Echocardiograms and signal-averaged ECGs were recorded on days 1,3,7, and 42 in 52 patients with a first anterior myocardial infarction. Twenty-nine percent of patients were late potential-positive on their initial signal-averaged ECG recorded on the day of admission. The incidence of late potentials rose during the next week to a peak of 42% at day 7, declining to 13% by day 42. The presence of late potentials on the day of admission was associated with an increase in end-diastolic volume index of 16.1 +/- 6.0 mL/m2 (mean +/- SEM), compared with a decreased of 4.7 +/- 2.7 mL/m2 among late potential-negative patients (P < .006). Qualitatively similar results were evident for late potentials on day 3 and day 7. By contrast, there was no association between late potentials on day 42 and ventricular dilatation. Marked dynamic changes in late potentials were evident during the first week. Patients with persistent late potentials (n = 9) on all three recordings in the first week showed a marked increase in end-diastolic volume index of 21.3 +/- 8.1 mL/m2 (P < .005 in comparison with patients who were persistently negative [n = 20]). Patients demonstrating dynamic positivity (n = 15) not present on all three recordings in the first week showed no significant increase in end-diastolic volume index. It is concluded that late potentials during the first week after infarction are associated with subsequent ventricular dilatation. These early-phase late potentials may be a manifestation of cell slippage. They arise before gross topographical enlargement and may serve as a predictor of ventricular dilatation.

Effect of infarct size measured from antimyosin single-photon emission computed tomographic scans on left ventricular remodeling

To evaluate the effect of infarct size on left ventricular volumes and geometric remodeling, 26 patients with a first acute Q wave myocardial infarction (anterior in 14, inferior in 12) had the infarct sized from single-photon emission computed tomographic (SPECT) imaging of indium-111 antimyosin. All patients underwent gated blood pool scintigraphy before hospital discharge for determination of ejection fraction and end-diastolic and endsystolic volume indexes. Infarct size was quantitated from indium-111 antimyosin uptake in coronal slices with use of a threshold technique for edge detection. Nineteen of 26 patients had additional simultaneous acquisitions of indium-111 and thallium-201 uptake and the infarct was expressed as a percent of the total left ventricle.Infarct size was larger (59 ± 16 vs. 33 ± 16 g), predischarge ejection fraction lower (35 ± 5% vs. 60 ± 9%) and end-systolic volume index higher (57 ± 13 vs. 36 ± 10 ml/m2) in the group with anterior infarction. Despite these differences, predischarge end-diastolic volume index was not significantly different between the group with anterior (88 ± 17 ml/m2) versus inferior (89 ± 14 ml/m2) infarction. There was a significant inverse correlation between percent infarct size and ejection fraction for patients with dual isotope imaging (r = −0.90) and a significant direct correlation between infarct size and end-systolic volume index (r = 0.79, p < 0.01).Fourteen patients without subsequent myocardial infarction or coronary artery bypass grafting had a repeat gated blood pool study late (26 ± 15 months) after infarction. Patients with an anterior infarction had a significant increase in end-diastolic volume index (+10 ± 11 ml/m2), which was also significantly different from the change in end-diastolic volume index in the group with inferior infarction (−5 ± 5.2 ml/m2).These data suggest that infarct size and location have a profound effect on left ventricular function and chamber size. Anterior infarcts, because they are larger, cause more severe left ventricular dysfunction and higher end-systolic volume early. The consequent increases in end-systolic wall stress may be the driving mechanism for late left ventricular chamber enlargement. This method for measuring infarct size has potential usefulness for selecting patients who will benefit from pharmacologic intervention to prevent late left ventricular dilation.

Prevention of late ventricular dilatation after acute myocardial infarction by successful thrombolytic reperfusion

To examine the sequential changes in left ventricular volume after thrombolytic therapy for acute myocardial infarction, gated radionuclide ventriculography was performed within 12 hours of thrombolysis and at 1 and 6 weeks in 34 consecutive patients who received intravenous thrombolytic therapy in the Thrombolysis in Myocardial Infarction Trial. Angiographic confirmation of immediate reperfusion (mean 5.6 hours after onset of symptoms) that persisted at 24 hours was noted in 24 patients; 10 patients were not reperfused. A small (9.5%), but significant (p = 0.05), increase in end-diastolic volume index was noted in the reperfused group between 1 and 6 weeks; however, a marked degree of dilatation (35%) was noted in the nonreperfused group (p = 0.01). The change in left ventricular volume between 1 and 6 weeks differed in the 2 groups for both end-diastolic volume index and end-systolic volume index (p = 0.01 and p = 0.02, respectively). By 6 weeks, both end-diastolic volume index and end-systolic volume index were greater in the nonreperfused group (p < 0.05). Between the acute and 6-week studies, definite increases in end-diastolic volume index (p < 0.05) and end-systolic volume index (p < 0.01) occurred commonly in the nonreperfused group but rarely in the reperfused group. Compared to the nonreperfused group, the reperfused group also had significantly higher ejection fractions at both 1 and 6 weeks (p < 0.05). The change in end-diastolic volume index between 1 and 6 weeks correlated significantly and inversely with the ejection fraction at 1 week (r = −0.60, p < 0.001). These results indicate that ventricular dilatation occurs between 1 and 6 weeks after myocardial infarction, is proportional to systolic dysfunction and may be largely prevented by successful thrombolytic reperfusion.