Delta Ejection Fraction Research Articles

First month global longtudinal strain for predicting early pacemaker-induced left ventricular dysfunction (PIVD) six month after pacemaker implantation

Abstract Background Pacemaker-induced ventricular dysfunction (PIVD) and pacemaker-induced cardiomyopathy (PICM) emerged as a complication following right ventricular permanent pacemaker (PPM) implantation, showing a great occurrence in the first year. Finding an early predictor of PIVD and PICM is crucial in order to alleviate mortality, morbidity, and increase health-care cost efficiency. Purposes to find new predictor by analyzing effect of first month GLS using 2D-speckle tracking echocardiography and reduction of left ventricular ejection fraction (LVEF), known as PIVD, in the first 6 month after PPM implantation. Methods A single center, prospective cohort study was conducted to all patients with normal LVEF, indicated for PPM implantation. Data of GLS was measured before and after one month of PPM implantation. Data of LVEF was measured before and six month after PPM implantation. The change of GLS in one month after PPM implantation was measured as delta GLS, and the change of LVEF in six month was measured as delta EF. Results Fifty-three patients from May 2018 until October 2020 was enrolled for this study based on inclusion and exclusion criteria. Patient’s baseline characteristics show 62±14 years of age, most of them had hypertension (54.7%) and had single chamber pacemaker implantation (81.1%). Study analysis reveals that ejection fraction (EF) reduce significantly after six months pacemaker implantation (66,5±5,6% become 60,7±10.7%; p= <0,00001). There were 6 patients (11.3 % ) suffering PICM. Correlation analysis between the change of GLS in the first month and the change of LVEF in the first six months after PPM implantation was statistically significant with moderate correlation (p<0.00001; r= -0.486). Linear regression analysis shows that every 1 point decrease of first month GLS, affecting 1.83 point decrease of sixth month LVEF (b= -0.1837, p=<0.00001). Conclusion There is significant moderate correlation between the change of GLS in the first month and early reduction of LVEF in the first 6 months after PPM implantation.The Scheme of Research Sampling Method

P3792The impact of elective cardioversion for atrial fibrillation in heart failure patients

Abstract Introduction Severe left ventricular systolic dysfunction (LVSD) is associated with worse outcomes in heart failure (HF) patients. Persistent atrial fibrillation (AF) is common in this patient group. As part of a nurse-led cardioversion service at a district general hospital we assessed the impact of elective cardioversion (DCCV) for AF in patients with LVSD on their ejection fraction (EF), and compared outcomes in patients selectively pre-treated with amiodarone for their DCCV. Methods A retrospective analysis was undertaken of DCCV for AF over 5 years, recording demographic, medication, serial echocardiogram (TTE), and outcome data. Significant LVSD was classified as moderate (ejection fraction [EF] 35–45%) or severe (EF<35%). All patients treated with amiodarone had baseline and serial thyroid, liver, renal function monitored, were counselled on side effects and followed up. Results 103 patients with significant LVSD and follow-up TTE underwent DCCV, with a median age of 66 (IQR 58–73) and mean CHA2DS2-VASc 2.5. Overall mean baseline EF was 30% (SD ±11), overall follow-up EF (regardless of repeat TTE rhythm) was 42% (SD ±12), and the mean delta EF +12% improvement (SD ±11). At follow-up TTE, 66% (68/103) of patients were in sinus rhythm (SR) and 34% (35/103) in AF. 62/68 (91%) patients in SR at follow-up TTE were also treated with HF medications, vs 33/35 (94%) of those in AF. 61/68 (90%) of patients in SR at follow-up TTE had any improvement in EF vs 21/35 (60%) patients in AF (p=0.0007). For patients in SR the mean baseline EF was 31% (SD ±10) and mean follow-up EF 47% (SD ±9), vs the AF at repeat TTE patients' mean baseline EF 27% (SD ±12) and mean follow-up EF 35% (SD ±13). The mean delta EF of patients still in SR at follow-up scan was 15% (SD ±10) vs 8% (SD ±11) for patients who had reverted to AF (p=0.0004). Prior analysis of our data-set including patients awaiting repeat TTE demonstrated a significant improvement in 6 month AF recurrence rate. Table 1. Comparing outcomes with amiodarone pre-treatment for patient with follow-up EF data Acute DCCV Success Mean Baseline EF Mean Repeat EF Mean Delta EF AF Recurrence to 6 months Amiodarone 17/17 (100%) 29% (SD 11) 45% (SD 11) 15% (SD 13) 6/17 (35%) No Amiodarone 80/86 (93%) 30% (SD 11) 42% (SD 12) 12% (SD 10) 50/86 (58%) P value 0.59 0.22 0.11 Conclusion Restoration of SR in a cohort of patients with AF, severe LVSD, on good medical therapy significantly improves left ventricular EF. This reinforces the importance of maintaining SR for HF patients. There was also a trend towards improved medium term outcomes in patients pre-treated with amiodarone. Further study into long-term rhythm control and ablation outcomes is needed.

Effects of Fimasartan/Amlodipine Fixed-Dose Combination on Left Ventricular Systolic Function and Infarct Size in Rat Myocardial Infarction Model.

The aim of this study was to evaluate the effects of fimasartan/amlodipine fixed-dosed combination (F/A) on left ventricle (LV) systolic function and infarct size in the rat myocardial infarction (MI) model. We induced MI in 20 rats by ligation of the left anterior descending coronary artery and they were divided into two groups [MI group (n=10) vs. MI+F/A 10 mg/kg group (n=10)]. F/A was administered for 28 days between day-7 and day-35 in the MI+F/A group and echocardiography was performed at day-7 and at day-35 after the induction of MI. Picrosirius red staining was performed to confirm the fibrotic tissue and infarct size was measured using image analysis program for Image J. At the 35-day follow-up, the LV ejection fraction (EF) was significantly higher (38.10±3.92% vs. 29.86±4.56%, p<0.001) and delta (day-35 minus day-7) EF was significantly higher (0.14±2.66% vs. −8.53±2.66%. p<0.001) in the MI+F/A group than the MI group. Systolic blood pressure was significantly lower in the MI+F/A group than the MI group (103.23±13.35 mmHg vs. 123.43±14.82 mmHg, p<0.01). The MI+F/A group had a smaller infarct size (26.84±5.31% vs. 36.79±3.10%, p<0.01) than the MI group at the 35-day follow-up. Oral administration of F/A 10 mg/kg could improve LV systolic function and reduce infarct size in a rat MI model.

Effects of Ivabradine on Left Ventricular Systolic Function and Cardiac Fibrosis in Rat Myocardial Ischemia-Reperfusion Model.

We evaluated the effects of Ivabradine on left ventricle (LV) ejection fraction (EF) and LV infarcted tissue in the rat myocardial ischemia-reperfusion model. Twenty rats were randomly assigned to group 1 (ischemia-reperfusion, no treatment, n=10) and group 2 (ischemia-reperfusion + Ivabradine 10 mg/kg, n=10). Ivabradine was administered for 28 days. Echocardiography was performed at 7 days and at 28 days after the induction of ischemia-reperfusion injury. Cardiac fibrosis induced by ischemia-reperfusion injury was evaluated by Masson's trichrome staining. The infarct size was quantified using the Image J program. At the 28-day follow-up, LVEF was significantly higher (36.02±6.16% vs. 45.72±2.62%, p<0.001) and fractional shortening was significantly higher (15.23±2.84% vs. 20.13±1.38%, p<0.001) in group 2 than group 1. Delta (28 day minus 7 day) EF was significantly higher in group 2 than group 1 (−4.36±3.49% vs. 4.31±5.63%, p<0.001). Also, heart rate (beats/min) was significantly lower in group 2 than group 1 (251.67±25.19 vs. 199.29±31.33, p=0.025). Group 2 had a smaller infarct size (40.70±8.94% vs. 30.19±5.89%, p<0.01) than group 1 at 28-day follow-up. Oral administration of Ivabradine could improve LV systolic function and reduce infarcted tissue area in rat myocardial ischemia-reperfusion model.

Predictive value of CMR criteria for LV functional improvement in patients with acute myocarditis.

We assessed the value of cardiovascular magnetic resonance (CMR) criteria ('Lake Louise Criteria') for predicting left ventricular (LV) functional improvement in patients with acute myocarditis. We studied 37 patients who referred for acute myocarditis during clinically acute myocarditis and after a 12-month follow-up. CMR sequences sensitive for oedema, hyperaemia, and irreversible injury were applied. Global and regional oedema were defined using published quantitative signal intensity (SI) cut-off values (area with an SI of >2 SD above visually normal myocardium). LV function was analysed using six long-axis views, with an increase of at least 5% of left ventricular ejection fraction considered as improvement. Out of a total of 37 patients, 29 met the CMR Lake Louise criteria (LL+) and eight did not (LL-). Baseline and 12-month ejection fraction (EF) were significantly lower in LL+ (53.2 ± 8 vs. 62.2 ± 5, P = 0.007 and 58.9 ± 4 vs. 62.9 ± 5, P = 0.045, respectively). At follow-up, EF increased in LL+ but remained unchanged within normal limits in LL- groups (delta EF: 5.7 ± 9.8 vs. 0.7 ± 2.0). The presence of global or regional myocardial oedema was strongly associated with an increase of EF ≥5%. In a multivariate analysis, the presence of global and/or regional oedema on admission was the only independent predictor of an increase of EF (P = 0.046). In patients with clinically suspected acute myocarditis, the presence of positive CMR criteria is associated with LV function recovery. Myocardial oedema as defined by CMR was the strongest parameter, indicating that the observed increase of EF may be due to the recovery of reversibly injured (oedematous) myocardium.

A Simple Electrocardiographic Predictor of Early Recovery of Left Ventricular Function in Stress Cardiomyopathy

Objective: To identify electrocardiographic parameters that predict extent of early improvement in ejection fraction (EF) in patients with stress cardiomyopathy. Methods: We collected baseline clinical, ECG and imaging data and follow up echocardiography data on 30 consecutive patients with stress cardiomyopathy. The relationship between baseline ECG parameters and Delta EF was evaluated by univariate and multivariable analysis. Results: Median EF improved from 35% to 55% (p Conclusion: The number of leads with T wave inversion is negatively correlated with and is an independent predictor of the extent of early improvement of EF in patients with stress cardiomyopathy. Hence the ECG at initial presentation can be used as a simple tool to predict LV function recovery.

Prognostic Value of Post-Ischemic Stunning as Assessed by Gated Myocardial Perfusion Single-Photon Emission Computed Tomography - A Subanalysis of the J-ACCESS Study -

To determine the prognostic value of post-ischemic stunning, the Japanese assessment of cardiac event and survival study by quantitative gated myocardial single-photon emission computed tomography (SPECT) (J-ACCESS) study was reevaluated. Of the 4,031 patients of the J-ACCESS, the present study evaluated 1,089 who completed gated SPECT both after stress and at rest. To assess post-ischemic stunning, the following measurements (left ventricular volumes after stress minus volumes at rest) were made: Deltaend-systolic volume (DeltaESV), Deltaenddiastolic volume (DeltaEDV) and Deltaejection fraction (DeltaEF). Myocardial stunning defined either as DeltaESV >or=5 ml, DeltaEDV >or=5 ml or DeltaEF <or=5% was observed in 21%, 22%, or 26%, respectively. During a 3-year follow-up, 101 cardiac events occurred. Kaplan-Meier survival estimation indicated worse event-free survival rates in patients with dilated ESV, dilated EDV, LVEF <or=45%, DeltaESV >or=5 ml or DeltaEDV >or=5 ml than in those without, whereas DeltaEF <or=5% did not predict events. Multivariate analysis demonstrated that LVEF <or=45% was the independent predictor for cardiac events. Nevertheless, DeltaEDV >or=5 ml was also an independent parameter, in addition to LVEF <or=45%, to predict the combined endpoint of cardiac death, myocardial infarction, and revascularization, but excluding heart failure. These results indicate that post-ischemic stunning, as assessed by gated SPECT, is a marker for poor prognosis, particularly for ischemic cardiac events.

The Impact of Exercise-Induced Changes in Intraventricular Dyssynchrony on Functional Improvement in Patients with Nonischemic Cardiomyopathy

The assessment of dynamic intraventricular dyssynchrony has been reported to be feasible in a clinical setting. However, its prognostic implication in functional improvement has not yet been investigated. Symptom-limited, supine bicycle exercise was performed on 41 patients with nonischemic cardiomyopathy (52 +/- 12 years, ejection fraction < 40%). Using Doppler tissue imaging, the average of peak systolic velocities at 6 basal segments was obtained at rest and peak exercise. Dyssynchrony index (Ts-SD12) was defined as the SD of the time to peak systolic velocities at 12 left ventricular segments. The percent change of end-systolic volume (%Delta ESV) was calculated at follow-up. A 15% or greater reduction in end-systolic volume (%Delta ESV < -15%) was considered as functional improvement. During exercise, changes in dyssynchrony (Delta Ts-SD12) were individually variable. Average of peak systolic velocities (V) at 6 basal segments at peak exercise independently correlated with Ts-SD12 at peak exercise (beta = -0.541, P < .001). Follow-up echocardiography was performed on 35 patients after medical treatment for 13.0 +/- 4.9 months. There was significant association of %Delta ESV with the change in mitral regurgitation (r = 0.434, P = .009), disease duration (r = 0.343, P = .045), QRS interval (r = 0.347, P = .041), and Delta Ts-SD12 (r = 0.511, P = .002). Multivariate analysis identified Ts-SD12 measured at peak exercise as the strongest predictor for functional improvement (%Delta ESV: beta = 0.577, P < .001; and Delta ejection fraction: beta = -0.563, P < .001). In patients with heart failure, dynamic dyssynchrony can be assessed during exercise. Ts-SD12 at peak exercise may be an independent predictor for reverse remodeling with medical treatment.

Valor pronóstico de las medidas seriadas de la functión ventricular izquierda y del rendimiento en el ejercicio en la insuficiencia cardiaca crónica

The prognostic value of a single measurement of ejection fraction and peak oxygen uptake in chronic heart failure has been extensively investigated. The aim of our study was to evaluate the prognostic significance of serial changes in ejection fraction and exercise performance in moderate to severe chronic heart failure. 182 patients (156 men, 53 [47-58] years) underwent echocardiography and cardiopulmonary exercise testing at baseline and after 10 [8-12] months. Most patients had idiopathic dilated cardiomyopathy (69%) and all patients presented left ventricular ejection fraction <45%. Median follow-up was 21 [14-34] months; cardiac death and heart transplantation were the end-points. Hazard ratio (HR, per unit) is presented with its 95% confidence interval (CI). During follow-up 18 patients (9.9%) died and 14 (7.7%) underwent heart transplantation. Baseline ejection fraction (HR, 0.94, 95% CI, 0.89-0.98 P=.006) and mitral regurgitation (HR, 4.22, 95% CI, 1.63-10.92, P=.003), and delta (second examination-baseline) ejection fraction (HR, 0.93, 95% CI, 0.88-0.98, P=.01) were the only significant variables at univariate analysis. Both ejection fraction and delta ejection fraction remained independently associated with events at multivariate analysis. The prognostic power significantly increased between a model including ejection fraction alone and another one including ejection fraction plus delta ejection fraction. In clinically stable patients with chronic heart failure, ejection fraction and its changes were independently associated with outcome; on the contrary, serial cardiopulmonary exercise testing did not provide significant prognostic value. Baseline plus changes in ejection fraction showed better prognostic performance than baseline ejection fraction alone.

Changes in Left Atrial Chamber Size Predicts Response to Beta-blocker Therapy in Patients with Dilated Cardiomyopathy

To clarify the relationship between left atrial (LA) and ventricular (LV) systolic function responded to beta-blocker (BB) in dilated cardiomyopathy (DCM), we investigated echocardiographic parameters before and 1, 3, 6, 12 months (M) after the initiation of carvedilol in 21 patients. NYHA class was improved in 15 patients (71%) during follow-up. LV ejection fraction (EF) was gradually increased (26.3±8.7 at baseline vs. 51.9±8.8% at 12 M, p<0.001) with significant decreased LV diastolic and LA dimensions (LAD: 51.2±7.9 at baseline vs. 45.2±9.2mm at 12M, p<0.01). Restrictive pattern of mitral flow, mitral regurgitation and enlarged LAD were improved in early stage. Figure showed a negative correlation between % of delta EF and delta LAD at 12 M. Decrease of LAD can predict the improvement of LV systolic function by BB therapy in DCM.

Stress-related variations in left ventricular function as assessed with gated myocardial perfusion SPECT

Background There is inconsistency in reported patient characteristics associated with differences in basal and poststress left ventricular function (delta ejection fraction [ΔEF]) assessed by gated single photon emission computed tomography (SPECT). This inconsistency may therefore hamper adequate interpretation. In this study we first determined the reproducibility of serial gated SPECT–assessed left ventricular function. Second, we determined whether left ventricular ejection fraction (LVEF) assessed directly after stress reflects basal LVEF and, if not, what patient characteristics were associated with this discrepancy in LVEF. Methods and results Serial reproducibility of technetium 99m tetrofosmin gated SPECT–assessed LVEF in 22 patients showed a mean difference between two sequential measurements at rest of 0.09% EF units, with a 95% limit of agreement (2 SDs) at 5.8% EF units. In 229 patients Tc-99m tetrofosmin gated SPECT was performed after stress and at rest. Independent predictors of ΔEF were the presence of scintigraphically proven ischemia (standardized coefficient, −1.256; P = .003) and difference in heart rate at the time of acquisition (standardized coefficient, 0.121; P = .001). Conclusions Gated SPECT–assessed LVEF at rest is reproducible under standard clinical conditions. However, LVEF assessed after stress does not represent LVEF at rest in patients with scintigraphically proven ischemia and in patients with increased heart rate after stress compared with heart rate at rest.

Cardiovascular hemodynamics and exercise tolerance in thyroid disease.

The heart is an organ sensitive to the action of thyroid hormone, and measurable changes in cardiovascular performance are detected with small variations in thyroid hormone serum concentrations. Most patients with thyroid disease experience cardiovascular manifestations, and the most serious complications of thyroid dysfunction occur as a result of cardiac involvement. The increased metabolic state and oxygen consumption that occur in hyperthyroid patients require an increased supply of oxygen and removal of metabolic products from the periphery. This is accomplished by increasing the cardiac output to meet the needs of the periphery. Circulation time is decreased in hyperthyroid patients, and a lowered arterial resistance and increased venous resistance promote the return of blood to the heart. Thyroid hormones may significantly decrease the strength of respiratory and skeletal muscles and affect regulatory mechanisms of adaptation to incremental effort. In hyperthyroidism, cardiovascular exercise testing and analysis of respiratory gas exchange demonstrate low efficiency of cardiopulmonary function as well as impaired chronotropic, contractile, and vasodilatatory reserves, which are reversible when euthyroidism is restored. During exercise, the increment (delta) of minute ventilation (respiratory rate x tidal volume), and oxygen pulse (oxygen uptake per heart beat) are significantly lower in dysthyroidism versus euthyroidism. Especially in older patients with thyroid dysfunction, markedly reduced workload, delta ejection fraction, and delta heart rate, both at the anaerobic threshold as well as at maximal exercise, are observed. In thyrotoxicosis, mitochondria oxidative dysfunction during exercise mostly causes intracellular acidosis, whereas in hypothyroidism, inadequate cardiovascular support appears to be one of the principal factors involved. These abnormalities partly explain why subjects with dysthyroidism are intolerant to exertion. Thus, in thyroid disease, both cardiac structures and function may remain normal at rest, however impaired cardiovascular and respiratory adaptation to effort becomes unmasked during exercise.

Stress echocardiography in hyperthyroidism.

Exertion symptoms occur frequently in subjects with hyperthyroidism. Using stress echocardiography, exercise capacity and global left ventricular function can be assessed noninvasively. To evaluate stress-induced changes in cardiovascular function, 42 patients with untreated thyrotoxicosis were examined using exercise echocardiography. Studies were performed during hyperthyroidism, after treatment with propranolol, and after restoration of euthyroidism. Twenty-two healthy subjects served as controls. Ergometry was performed with patients in a semisupine position using a continuous ramp protocol starting at 20 watts/min. In contrast to control and euthyroidism, the change in end-systolic volume index from rest to maximal exercise was lower in hyperthyroidism. At rest, the stroke volume index, ejection fraction, and cardiac index were significantly increased in hyperthyroidism, but exhibited a blunted response to exercise, which normalized after restoration of euthyroidism. Propranolol treatment also led to a significant increase of delta (delta) stroke volume index. Maximal work load and delta heart rate were markedly lower in hyper- vs. euthyroidism. Compared to the control value, systemic vascular resistance was lowered by 36% in hyperthyroidism at rest, but no further decline was noted at maximal exercise. The delta stroke volume index, delta ejection fraction, delta heart rate, and maximal work load were significantly reduced in severe hyperthyroidism. Negative correlations between free T3 and diastolic blood pressure, maximal work load, delta heart rate, and delta ejection fraction were noted. Thus, in hyperthyroidism, stress echocardiography revealed impaired chronotropic, contractile, and vasodilatatory cardiovascular reserves, which were reversible when euthyroidism was restored.

Gender-related differences in left ventricular filling dynamics in older subjects after endurance exercise training.

The present study was designed to determine if gender affects the adaptive response to endurance exercise training of left ventricular filling dynamics in older individuals. Recently, it was shown that gender influences the cardiovascular responses to endurance exercise training in older subjects. Older men improve left ventricular systolic performance and increase maximal cardiac output in response to endurance exercise training, whereas older women do not. Twelve men (65 +/- 1 years old; mean +/- SE) and 10 women (64 +/- 1) were studied before and after 9 months of endurance exercise training. Maximal O2 uptake was determined during treadmill exercise. Left ventricular filling dynamics and ejection fraction (EF) at rest and during supine exercise were assessed by Tc-99m radionuclide ventriculography. When expressed relative to body weight, maximal O2 uptake (VO2 max) was increased by 24% (27.3 +/- 1.5 to 34.0 +/- 1.5 ml/kg/min; p < .01) in men and 27% (21.9 +/- 1.0 to 27.8 +/- 1.0 ml/kg/min; p < .01) in women in response to endurance exercise training. In men, the time-to-peak filling rate (TPFR) decreased (-19.8 +/- 6.7 ms; p < .05) during exercise at a comparable heart rate in response to training. In contrast, the change in TPFR in women (+2.7 +/- 6.0 ms) was small and insignificant. Peak filling rate (PFR) at rest and during exercise was similar before and after training in men and women. The change in left ventricular systolic reserve at a comparable heart rate from pre-to posttraining improved in men (delta EF 4 +/- 3%; p < .05), but not in women (-2 +/- 3%). The results indicate that the adaptive response of left ventricular filling dynamics to endurance exercise training is influenced by gender in older subjects. Older men show improvement in left ventricular filling dynamics, whereas older women do not.

The use of intraaortic balloon pumping as an adjunct to reperfusion therapy in acute myocardial infarction

To assess the risk and possible benefits of use of the percutaneous IABP in patients given thrombolytic therapy as treatment for acute myocardial infarction, we prospectively evaluated 810 consecutive patients entered into the TAMI trials. During hospitalization the 85 patients treated with the IABP had more cardiac risk factors, were slightly older (58 vs 56 years), and more often had anterior infarction (62% vs 38%). At acute cardiac catheterization, patients treated with the IABP also had more multivessel coronary disease (67% vs 43%), more frequent TIMI grade 0 or 1 flow (44% vs 28%), lower global ejection fraction (40% vs 52%), and worse regional infarct (−3.2 vs −2.5 SD/chord) and noninfarct (−0.67 vs + 0.36 SD/chord) zone function. Although mortality rates (32% vs 4%) and in-hospital complications were greater in patients treated with the IABP, a greater improvement in global (delta ejection fraction: + 1.9% vs +0.7%) and noninfarct zone (delta SD/chord: +0.11 vs −0.09) left ventricular function was observed in patients treated with the IABP at 1-week follow-up angiography. In addition, no reinfarction or reocclusion of the infarct-related artery occurred while patients were being treated with the IABP. These results suggest that the IABP may have a specific role after thrombolytic therapy in treating patients at high risk for reocclusion or at high risk for hemodynamic deterioration because of large infarction or critical stenoses in coronary vessels supplying the noninfarct zone.

Consequences of reocclusion after successful reperfusion therapy in acute myocardial infarction. TAMI Study Group.

To determine the clinical consequences of reocclusion of an infarct-related artery after reperfusion therapy, we evaluated 810 patients with acute myocardial infarction. Patients were admitted into four sequential studies with similar entry criteria in which patency of the infarct-related artery was assessed by coronary arteriography 90 minutes after onset of thrombolytic therapy. Successful reperfusion was established acutely in 733 patients. Thrombolytic therapy included tissue-type plasminogen activator (t-PA) in 517, urokinase in 87, and a combination of t-PA and urokinase in 129 patients. All patients received aspirin, intravenous heparin and nitroglycerin, and diltiazem during the recovery phase. A repeat coronary arteriogram was performed in 88% of patients at a median of 7 days after the onset of symptoms. Reocclusion of the infarct-related artery occurred in 91 patients (12.4%), and 58% of these were symptomatic. Angiographic characteristics at 90 minutes after thrombolytic therapy that were associated with reocclusion compared with sustained coronary artery patency were right coronary infarct-related artery (65% versus 44%, respectively) and Thrombolysis in Myocardial Infarction (TIMI) flow 0 or 1 (21% versus 10%, respectively) before further intervention. Median (interquartile value) degree of stenosis in the infarct-related artery at 90 minutes was similar between groups: 99% for reoccluded (value, 90/100%) compared with 95% for patent (value, 80/99%). Patients with reocclusion had similar left ventricular ejection fractions compared with patients with sustained patency at follow-up. However, patients with reocclusion at follow-up had worse infarct-zone function at -2.7 (value, -3.2/-1.8) versus -2.4 (SD/chord) (value, -3.1/-1.3) (p = 0.016). The recovery of both global and infarct-zone function was impaired by reocclusion of the infarct-related artery compared with maintained patency; median delta ejection fraction was -2 compared with 1 (p = 0.006) and median delta infarct-zone wall motion was -0.10 compared with 0.34 SD/chord (p = 0.011), respectively. In addition, patients with reocclusion had more complicated hospital courses and higher in-hospital mortality rates (11.0% versus 4.5%, respectively; p = 0.01). We conclude that reocclusion of the infarct-related artery after successful reperfusion is associated with substantial morbidity and mortality rates. Reocclusion is also detrimental to the functional recovery of both global and infarct-zone regional left ventricular function. Thus, new strategies in the postinfarction period need to be developed to prevent reocclusion of the infarct-related artery.

Pulmonary thallium uptake: Correlation with systolic and diastolic left ventricular function at rest and during exercise

Quantified pulmonary 201-thallium uptake, assessed as pulmonary/myocardial ratios (PM) and body surface area-corrected absolute pulmonary uptake (Pc), was determined from single photon emission computed tomography studies in 22 normal subjects and 46 consecutive patients with coronary artery disease (CAD). By means of equilibrium radionuclide angiography (ERNA), ejection fraction (EF), peak ejection rate (PER) in end-diastolic volume (EDV/sec) and peak filling rate (PFR) in EDV/sec and stroke volume (SV/sec) units, PFR/PER ratio, and time to peak filling rate (TPFR) in milliseconds were computed at rest and during exercise (n = 35). Left ventricular response to exercise was assessed as delta EF, relative delta EF, delta EDV, and delta ESV. In normal subjects the PM ratios showed significant inverse correlation with PER at rest and with EF, PER, and PFRedv during exercise. For the left ventricular response to exercise, delta ESV showed significant correlation with the PM ratios. The body surface area-corrected pulmonary uptake values showed no correlation with any of the variables. In patients with CAD the PM ratios and Pc uptake showed significant inverse correlation with EF, PER, PFRedv and to exercise EF, exercise PER, and exercise PFRedv. For the left ventricular response to exercise, delta EF showed significant inverse correlation with the PM ratios but not with the Pc uptake. Neither in normal subjects nor in patients with CAD did any of the independent diastolic variables show significant correlation with the PM ratios or Pc values. Thus pulmonary thallium uptake is correlated with systolic left ventricular function at rest and during exercise in normal subjects and in patients with CAD but not with diastolic function. In normal subjects delta ESV and in patients with CAD, delta EF showed correlation with pulmonary thallium uptake.

Interaction between left ventricular end-diastolic and end-systolic volumes in normal humans

The extent to which the end-systolic volume (ESV) "follows" the end-diastolic volume (EDV) when the latter changes in response to various perturbations is a major determinant of the cardiac ejection fraction (EF) and has not been studied in humans. We measured EDV, ESV, and EF, determined by gated blood pool scans, during a change in posture from the supine to the upright seated position and during graded upright bicycle exercise. The experimental group consisted of 119 healthy individuals (79 males and 40 females) ranging in age from 21 to 81 yr and in physical-conditioning status (75-225 W maximum work load); rigorous screening excluded cardiac disease. Multiple regression analysis showed that the change in ESV (delta ESV) during a postural shift or during graded exercise was highly statistically correlated with the change in EDV (delta EDV) that occurred (r2 ranged from 0.34 to 0.49, correlation is positive) regardless of age, sex, or exercise work load. The correlation of delta ESV with delta EDV observed in this large sample, heterogeneous with respect to age, sex, and physical fitness, was also present in additional 31 subjects who exercised during beta-adrenergic blockade (propranolol 0.15 mg/kg). The delta EF with posture change and exercise in all subjects under all conditions was highly and inversely correlated with the delta ESV (r2 ranged from 0.38 to 0.81). Thus the delta ESV during the circulatory adaptive response to orthostatic and exercise stresses in humans is related to the delta EDV, and this relationship modulates the delta EF in response to these stresses.

Assessment of relationship between the pattern of hypertrophy and the function of left ventricle in patients with chronic aortic regurgitation.

Pre- and postoperative echocardiograms of 64 patients with chronic aortic regurgitation who had undergone isolated aortic valvular replacement (AVR) were studied. These patients were divided into 3 groups as follows: (1) Group A patients who had preoperative end-diastolic radius to wall thickness ratio (R/Thd) less than or equal to 3. (2) Group B1 patients who had preoperative R/Thd greater than 3 and end-systolic radius to wall thickness ratio (R/Ths) less than 2. (3) Group B2 patients who had preoperative R/Thd greater than 3 and R/Ths greater than or equal to 2. Using this classification we assessed the relation between the pattern of hypertrophy and left ventricular (LV) function and the reversibility of LV dysfunction following AVR. Preoperatively, ejection fraction (EF) during handgrip exercise was unchanged in Group A (% delta EF: -2.8 +/- 7.1%) and significantly decreased in Groups B1 (-17.0 +/- 5.8%) and B2 (-20.2 +/- 4.6%). In the late postoperative period, however, it was, -1.2 +/- 3.3%, -2.0 +/- 4.6%, and -17.7 +/- 8.6% in Groups A, B1, B2, respectively. Preoperatively the slope of end-systolic wall stress/volume (ESWS-ESV relation was 1.96 +/- 0.43 in Group A (p less than 0.01 vs Group B2, NS vs Group B1), 1.54 +/- 0.38 in Group B1 (NS vs Group B2) and 1.17 +/- 0.47 in Group B2. It was stressed that a good relationship existed between the pattern of hypertrophy and function as well as the reversibility of LV dysfunction following AVR.

Equilibrium Radionuclide Angiocardiography to Select Inotropic Therapy in Patients with Left Ventricular Aneurysm

Fourteen patients with postinfarctual ventricular aneurysm underwent equilibrium radionuclide angiocardiography at rest (ERNA) before and after oral digoxin administration in order to evaluate the effects of increasing myocardial contractility upon both ventricular aneurysm mechanical behaviour and global ventricular function. The ejection fraction (EF) was not significantly affected by digoxin therapy. However, digoxin induced changes in EF (delta EF) correlated inversely with changes in aneurysm size and directly with changes in the extent of the hypokinetic area. Two types of aneurysm were observed: high-compliance aneurysm the size of which increased after digoxin administration while both EF and the extent of the hypokinetic area fell, and low compliance aneurysm for which opposite changes occurred. This different behaviour of ventricular aneurysm may have important practical implications as surgery would be probably more effective than medical treatment in improving resting ventricular function in patients with high-compliance aneurysm.