Abnormal Interventricular Septal Motion Research Articles

The role of electrocardiographic findings in pulmonary embolism risk assessment

Abstract Funding Acknowledgements Type of funding sources: None. Introduction The electrocardiogram (ECG) is helpful in patients (P) with pulmonary embolism (PE), but it is not present in the existing risk prediction tools, such as the Pulmonary Embolism Severity Index (PESI). Intermediate risk PE encompasses a heterogeneous group of P, with different prognoses, some of whom will need fibrinolytic treatment. This study aims to determine the prognostic impact of ECG in intermediate-risk PE. Methods All P admitted for intermediate-risk PE in an Intensive Cardiac Care Unit between 2007 and 2016 were included. P were followed up for two years for all-cause mortality. Clinical and analytical variables, ECG, echocardiographic, and computed tomography (CT), were collected. Statistical analysis used chi-square and Mann-Whitney U tests, binary logistic regressions, Kaplan-Meier curves, and Cox regression. Results This study included 209 P: mean age 63±18years; 38.5% male. T-wave inversion in leads V1-V3 was present in 81 (38.8%), S1Q3T3 pattern in 51 (24.4%), incomplete right bundle branch block (RBBB) in 27 (12.9%), and complete RBBB in 22 (10.5%). T-wave inversion in leads V1-V3 was associated with syncope at presentation (p=0.032); presence of echocardiographic right ventricle dilation (p=0.003) and abnormal interventricular septal (IVS) motion (p=0.001). S1Q3T3 pattern was associated with syncope (p=0.028); higher heart rate at admission (p=0.001); higher troponin (p=0.013) and BNP (p=0.010) levels; abnormal IVS motion (p=0.004); and increased CT-derived right-to-left ventricle diameter (RV/LV) ratio (p=0.014). RBBB were associated with syncope (p=0.020); higher troponin and BNP levels (p=0.001); and increased RV/LV ratio (p=0.029). For each increase in the number of these ECG findings, there was an increase in the odds of fibrinolytic treatment (OR 1.573, 95%CI 1.150-2.151, p=0.005), and the number of ECG findings was a predictor of fibrinolysis independently from PESI (OR 1.535, p=0.008). In survival analysis, T-wave inversion in leads V1-V3 was associated with decreased survival during follow-up (x2=4.398; p=0.036), even after adjustment for PESI (OR 0.322, p=0.041). Conclusions ECG findings of PE were associated with clinical, analytical and imagiological risk features. They were also predictors of fibrinolysis, and T-wave inversion in leads V1-V3 was associated with decreased survival after adjustment for PESI. Therefore, in the future, incorporation of ECG findings in risk scores might allow better risk assessment in intermediate-risk PE.

Echocardiographic investigation of the mechanism underlying abnormal interventricular septal motion after open heart surgery.

BackgroundAbnormal interventricular septal motion (ASM) is frequently observed after open heart surgery (OHS). The aim of this study was to investigate the incidence and temporal change of ASM, and its underlying mechanism in patients who underwent OHS using transthoracic echocardiography (TTE).MethodsIn total, 165 patients [60 ± 13 years, 92 (56%) men] who underwent coronary bypass surgery or heart valve surgery were consecutively enrolled in a prospective manner. TTE was performed preoperatively, at 3--6-month postoperatively, and at the 1-year follow-up visit. Routine TTE images and strain analysis were performed using velocity vector imaging.ResultsASM was documented in 121 of 165 patients (73%) immediately after surgery: 26 patients (17%) presented concomitant expiratory diastolic flow reversal of the hepatic vein, 11 (7%) had inferior vena cava plethora, and 11 (7%) had both. Only 2 patients (1%) showed clinically discernible constriction. ASM persisted 3--6 months after surgery in 38 patients (25%), but only in 23 (15%) after 1 year. There was no difference in preoperative and postoperative peak systolic strain of all segments of the left ventricle (LV) between groups with or without ASM. However, systolic radial velocity (VRad) of the mid anterior-septum and anterior wall of the LV significantly decreased in patients with ASM.ConclusionAlthough ASM was common (74%) immediately after OHS, it disappeared over time without causing clinically detectable constriction. Furthermore, we consider that ASM might not be caused by myocardial ischemia, but by the decreased systolic VRad of the interventricular septum after pericardium incision.

MR-derived right ventricular parameters can predict pulmonary hypertension

Right heart catheterization (RHC) is required for definitive diagnosis of pulmonary hypertension (PH) and serial echocardiograms or RHC are necessary for long term disease management. However, RHC is invasive, costly and risky for the patient[1]. Echocardiography is a non-invasive alternative but recent studies have questioned its accuracy and reproducibility in the setting of PH[2]. Cardiac magnetic resonance (CMR) has been shown to be helpful in distinguishing PH patients from healthy subjects through visualization of morphologic features such as right atrial and ventricular enlargement, tricuspid regurgitation and abnormal interventricular septal motion[3]. CMR has the additional advantage of producing quantitative measures of right ventricular function, which may have added value in assessing PH.

Understanding Late Gadolinium Enhancement in Pulmonary Hypertension

A 68-year-old woman with a 3-year history of breathlessness (World Health Organization functional class III) was diagnosed with idiopathic pulmonary arterial hypertension. Investigations included a 12-lead ECG, chest radiograph, and computed tomography scan of the thorax (Figure 1, A-C). At cardiac catheterization, mean pulmonary arterial pressure and pulmonary vascular resistance were elevated (73 mm Hg and 1545 dyne · s · cm−5, respectively), and cardiac index was reduced (1.9 L/min/m2). A solitary 60% left circumflex coronary artery stenosis was present. Cardiovascular magnetic resonance identified right ventricular (RV) hypertrophy (indexed mass of 64 g/m2; normal=16 to 36 g/m2), right ventricular systolic dysfunction (RV ejection fraction 31%; normal >57%), and paradoxical interventricular septal (IVS) motion. Late gadolinium-enhanced (LGE) images taken 10 minutes after injection of 0.1 mmol/kg gadolinium–diethylenetriamine pentaacetic acid showed enhancement of both insertion regions (Figure 2A, 2B, and 2D). Figure 1. A, Twelve-lead ECG: …

The Impacts of Transcatheter Occlusion for Congenital Atrial Septal Defect on Left Ventricular Systolic Synchronicity: A Three-Dimensional Echocardiography Study

To investigate the impacts of transcatheter occlusion for congenital atrial septal defect (ASD) on left ventricular (LV) systolic synchronicity using a real time three-dimensional echocardiography (RT3DE). Thirty patients with ASD closure were recruited for the study. Realtime three-dimensional echocardiographic data sets were acquired for the measurement of LV volumes LV ejection fractions and LV three-dimensional systolic synchronicity before and at 6 months after transcatheter occlusion for ASD. M-mode echocardiography and RT3DE were performed to characterize interventricular septal (IVS) motion. There were no differences in LV systolic synchronicity between before and after transcatheter closure of ASD (Tmsv-16SD%: 5.6%+/- 1.4% vs 5.8%+/- 1.8%, P > 0.05; Tmsv-12SD%: 5.2 +/- 1.1% vs 5.4 +/- 1.2%, P > 0.05). But the abnormal IVS motion was found before device closure and normalized after transcatheter occlusion for ASD using M-mode echocardiography and the excursion-time figure (bull's-eye derived from RT3DE); At the same time, LV ejection fraction (59.8 +/- 2.6 vs 66.7 +/- 5.9, P < 0.05) stroke volume (49 +/- 14 vs 63 +/- 11, P < 0.05) was improved significantly as well as normalization of IVS motion after transcatheter occlusion for ASD. The correlation between ASD diameter and change of LVEF is significant (r = 0.85, P < 0.001). Although transcatheter occlusion did not significantly impact on intrinsic LV systolic synchronicity in patients with ASD, LV systolic function can be improved through normalization of IVS abnormal motion after transcatheter ASD occlusion.

Evaluation of left ventricular diastolic function using color kinesis.

Color kinesis (CK) is a real-time echocardiographic technique based on acoustic quantification that yields regional and global information by tracking and color-encoding endocardial motion. The aim of this study was to determine the feasibility and usefulness of diastolic CK images with ICK software to objectively assess global and regional left ventricular (LV) diastolic function. Accordingly, diastolic properties obtained from CK images were compared with conventional Doppler echocardiographic indices. We studied 56 subjects who underwent echocardiographic evaluation in our laboratory for assessment of cardiac structure and function. Criteria for inclusion included the presence of normal sinus rhythm and adequate two-dimensional echocardiographic imaging. Exclusion criteria were (1) all types of arrhythmias, (2) pericardial effusion, (3) heart rates <55 or >90 beats/min, (4) abnormal interventricular septal motion caused by right ventricular pressure or volume overload, (5) moderate to severe mitral or aortic regurgitation, and (6) mitral valve stenosis. Using pulsed Doppler echocardiography, peak velocities during rapid filling (E) and atrial contraction (A) were measured, and the E/A ratio and deceleration time of the E wave velocity (DT) were calculated. The time-velocity integral (TVI) of the E wave (TVI-R), A wave (TVI-A), and rapid-filling fraction (TVI-R/TVI-R+TVI-A) was measured. The early diastolic mitral annular velocity (Ea) was measured by tissue Doppler. The 56 subjects were divided into the following three groups: (1) an impaired relaxation group consisting of 30 patients with normal ejection fraction and a mitral inflow pattern with a reduced E/A ratio (E/A < 1.0); (2) a pseudonormal group consisting of 18 patients with a mitral inflow pattern with an increased E/A ratio (E/A > 1.0), an increased E/Ea ratio (E/Ea 10), and no shortened DT (≧140 ms) [patients with hypertrophic cardiomyopathy (HCM, n = 8), dilated cardiomyopathy (DCM, n = 8), and aortic valve stenosis (n = 2) were included in this group); and (3) a restrictive group consisting of eight patients with a mitral inflow pattern with an increased E/A ratio (E/A >1.5), an increased E/Ea ratio (E/Ea ≧10), and a shortened DT (<140 ms) [patients with DCM (n = 5) and HCM (n = 3) were included in this group]. As a control group, 20 normal subjects (30 ± 18 years) were selected on the basis of having high-quality echocardiographic images. Diastolic CK images were obtained from the LV midpapillary short-axis view. The analysis of CK diastolic images was performed by using ICK software. The CK-diastolic index (CK-DI) was defined as the degree of LV segmental expansion during the first 30% of diastole, expressed as a percentage. The mean CK-DI was calculated from the average CK-DI of six LV segments. No relationship was observed between mean CK-DI and rapid-filling fraction in any of the study subjects (r = -0.092, P > 0.2). Mean CK-DI was significantly lower in the restrictive group (34.2% ± 4.3%) compared with the normal group (70.6% ± 7.4%), the impaired relaxation group (50.5% ± 7.7%), and the pseudonormal group (42.3% ± 7.5%). The reduction of mean CK-DI was found to be associated with the progression of LV diastolic dysfunction. We conclude that the analysis of diastolic CK by using ICK software is a useful technique that can be applied to quantitative evaluation of LV global diastolic function.

Regression of left ventricular mass and wall thickness after cardiac resynchronization therapy: proof of pathophysiological conceptThe opinions expressed in this article are not necessarily those of the Editors of the European Heart Journal or of the European Society of Cardiology.

Cardiac resynchronization therapy (CRT) has become an established therapy for patients with NYHA class 3 and 4 heart failure, with a left ventricular (LV) ejection fraction (EF) 120 ms, especially in patients with a complete left bundle branch block (CLBBB).1 A number of studies have shown that patients with these characteristics may benefit from this therapy in terms of quality-of-life (QoL), exercise capacity, LV function, LV dimensions/volumes, morbidity, and even mortality.1 The key to understanding these effects lies in the term asynchrony as the most important determinant for success of CRT. Asynchrony, which means that parts of the heart and particularly the LV are out of phase during LV contraction and relaxation, can occur at three levels within the heart: atrioventricular (timing of atrial contraction to LV and RV contraction and relaxation, interventricular (between LV and RV), and intraventricular (between different segments of the LV). Asynchrony leads to several deleterious pathophysiological effects: abnormal interventricular septal wall motion, increased regional/global wall stress, reduced d P /d t , reduced pulse pressure, reduced EF and cardiac output, increased LV dimensions/volumes, LV regional hypertrophy, reduced diastolic filling time, increased mitral regurgitation, increased myocardial oxygen consumption, and decreased cardiac energetic efficiency. The final common pathway of all these effects is overt clinical heart failure with its inherent loss of QoL, hospital readmissions, and mortality.1 CRT may abolish and even reverse several, and sometimes all of these effects. If the effects of CRT are to be evaluated it is important … *Corresponding author. Tel: +31 204442244; fax: +31 204442446. E-mail address : hermanmannaerts{at}wanadoo.nl

Doppler tissue imaging improves assessment of abnormal interventricular septal and posterior wall motion in constrictive pericarditis

We hypothesized that Doppler tissue imaging in the short axis would provide enhanced quantitative information for differentiating the pattern and extent of abnormal septal and posterior wall motion in constrictive pericarditis (CP). Using quantitative pulsed wave and color M-mode Doppler tissue imaging, we quantified the pattern of abnormal septal and posterior wall motion and studied its incremental advantage over conventional M-mode and 2-dimensional echocardiography in 40 patients with surgically proven CP. The pattern and extent of abnormalities were compared with 35 age- and sex-matched control subjects and 20 patients with abnormal septal motion of other causes. In 33 patients (82.5%) with CP, the interventricular septum showed high-velocity (>7 cm/s) early diastolic biphasic motion with or without multiple recoil waves (polyphasic diastolic septal fluttering). In the posterior wall, the early diastolic wave was normal but the late diastolic wave was reduced in 24 patients (60%) and absent in 7 (17.5%). In comparison, M-mode and 2-dimensional echocardiography identified abnormal septal or posterior wall motion in 24 patients (60%) ( P = .003). The pattern of abnormal septal motion in CP could be differentiated from abnormal septal motion of other causes in 16 patients (80%). The overall sensitivity and specificity of high-velocity polyphasic septal flutter for differentiating CP from control cases and other diseases was 82.5% and 92.7%, respectively. In CP, Doppler tissue imaging in the short axis provides unique diagnostic information and reliably differentiates CP from control cases and most other causes of abnormal septal motion.

Rationale and design of a randomized clinical trial to assess the safety and efficacy of cardiac resynchronization therapy in patients with advanced heart failure: The Multicenter InSync Randomized Clinical Evaluation (MIRACLE)

Up to 50% of patients with chronic systolic heart failure have interventricular conduction delays, such as left bundle branch block, that result in abnormal electrical depolarization of the heart. Prolonged QRS duration results in abnormal interventricular septal wall motion, decreased contractility, reduced diastolic filling time, and prolonged duration of mitral regurgitation, which places the failing heart at a significant mechanical disadvantage. Prolonged QRS duration has been associated with poor outcome in heart failure patients. Atrial-synchronized, biventricular pacing or cardiac resynchronization therapy optimizes atrial-ventricular delay, narrows QRS duration, and seems promising in the management of advanced heart failure patients. Initial studies show improved quality of life and functional capacity compared with baseline or with no pacing. These studies, however, were either uncontrolled or poorly controlled, unblinded or only single-blinded, and enrolled small numbers of patients. The Multicenter InSync Randomized Clinical Evaluation (MIRACLE) is a large, prospective, randomized, double-blind, controlled trial designed to more definitively evaluate the clinical efficacy and safety of cardiac resynchronization for heart failure. The study is being completed in 3 phases (an initial pilot phase, a pivotal phase, and an expansion phase), enrolling 500 patients with New York Heart Association (NYHA) class III and IV systolic heart failure and QRS durations of 130 ms or more. Prospectively defined primary end points for the pivotal phase include evaluation of safety (implant success rate, freedom from stimulator- and ventricular-lead-related complications) and effects on functional status (quality of life, NYHA class, 6-minute hall walk distance) at 6 months. A variety of secondary end points will further define the efficacy and mechanism(s) of action of cardiac resynchronization in heart failure. The pivotal phase of MIRACLE will conclude in January 2001.

82-Year-Old Man With Recurrent Syncope

82-Year-Old Man With Recurrent Syncope

Cross sectional echocardiographic demonstration of the mechanisms of abnormal interventricular septal motion in congenital total absence of the left pericardium.

OBJECTIVE: To investigate the influence of the absence of the pericardium on the left ventricular wall, particularly on interventricular septal motion, using M mode and cross sectional short axis echocardiography...

Abnormal postoperative interventricular motion: New intraoperative transesophageal echocardiographic evidence supports a novel hypothesis

Abnormal interventricular septal motion is a frequent finding after cardiac surgery. However, the time course and underlying mechanisms are not well understood. Nineteen patients, mean age 54 years (range 20 to 82 years), were studied with intraoperative transesophageal echocardiography at five specific times: with the chest closed (baseline), with the chest open and the pericardium closed, with both chest and pericardium open, after cardiopulmonary bypass with the chest open, and after cardiopulmonary bypass with the chest closed. In each patient interventricular septal motion was recorded from the transgastric view; tricuspid annular motion and Doppler color flow mapping of tricuspid regurgitation were obtained from the four-chamber view. All the echocardiographic data were stored on videotape and were later viewed in random sequence by one investigator who was aware of the baseline stage but was blinded to the other stages. All patients had normal septal motion before cardiopulmonary bypass. After cardiopulmonary bypass, with the chest still open, 5 of 17 patients (29%) with adequate recordings had abnormal septal motion while 13 of 17 patients (76%) with adequate recordings had abnormal tricuspid annular motion. After chest closure, only three patients (14%) had normal septal motion and one patient (6%) had normal tricuspid annular motion. Significant tricuspid regurgitation was an infrequent finding in all cases. It is concluded that abnormal interventricular septal motion occurs after cardiopulmonary bypass and is related to abnormal tricuspid annular motion. We hypothesize that suboptimal right ventricular myocardial preservation impairs the motion pattern of the right ventricle, including the tricuspid annulus.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship between septal perfusion, viability, and motion before and after coronary artery bypass surgery

The etiology of abnormal interventricular septal motion occurring after open-heart surgery using cardiopulmonary bypass has not been clarified. Intraoperative ischemic septal injury has been proposed as one explanation for this finding. To examine this possibility, resting septal perfusion and viability were studied using rest and redistribution thallium-201 scintigraphy in 16 patients before and after coronary artery bypass surgery. The results were compared with septal motion on preoperative and postoperative resting gated blood pool scans. Preoperatively, septal thallium uptake was normal in 10 of 16 patients, and septal motion was normal in 14 of 16. Postoperatively, septal thallium uptake was normal in 11 of 16 patients, while septal motion was abnormal in all. Thus abnormal postoperative septal motion is usually associated with normal septal perfusion and viability on thallium scans and therefore is not the result of septal ischemic injury in a majority of patients.

Left ventricular function in rheumatic mitral stenosis

Haemodynamic factors contributing to clinical disability in patients with rheumatic mitral stenosis have been under discussion and investigation for decades. Prior to the development of left heart catheterization, a low cardiac output in the presence of little or no pulmonary hypertension was taken as evidence for a myocardial 'insufficiency'. With the use of left heart catheterization, it was possible to exclude the presence of coronary artery disease and to assess directly the size and function of the left ventricle. Such studies indicate a tendency toward low-normal left ventricular end-diastolic volumes and low-normal ejection fractions. Modest reductions in the ejection fraction may be due to: (1) a restriction or tethering of posterobasal myocardium by the scarred mitral apparatus, or (2) abnormal interventricular septal motion related to right ventricular overload and unequal filling of the two ventricles. These and other factors, such as limited LV distensibility and variable diastolic suction, may affect ventricular function in rheumatic mitral stenosis. Thus, left ventricular dysfunction can generally be explained without implicating a rheumatic myocardial factor.

Abnormal septal motion after aortic valve replacement for chronic aortic regurgitation: no evidence for myocardial ischaemia by exercise radionuclide angiography

To evaluate interventricular septal motion and left ventricular function after aortic valve replacement for chronic aortic regurgitation, we studied 12 patients at rest and during exercise by radionuclide angiography after a mean of 19 (range 12-36) months after operation (group I). Twenty patients with chronic aortic regurgitation without aortic valve replacement served as controls (group II). None of the patients had coronary artery disease as documented by arteriography. Abnormal interventricular septal motion at rest was seen in 11 patients of group I, of whom 8 showed hypokinesis and 3 akinesis. During exercise, the interventricular septal wall motion improved in 4 patients, worsened in 3 patients and did not change in 5 patients. All patients of group II had normal interventricular septal motion at rest. During exercise, 5 patients showed septal wall hypokinesia together with apical and posterolateral wall motion abnormalities. The left ventricular ejection fraction at rest was 62% +/- 20% in group I and 66% +/- 8% in group II (not significant). During exercise, the left ventricular ejection fraction was 59% +/- 24% in group I and 68% +/- 13% in group II (not significant). We conclude that abnormal interventricular septal motion at rest is commonly found in patients with aortic valve replacement for chronic aortic regurgitation. During exercise, septal wall motion in the patients with aortic valve replacement shows a variable response from complete normalization to akinesia. These findings are mostly associated with a normal global left ventricular function both at rest and during exercise, which precludes myocardial ischaemia as a primary cause for abnormal septal wall motion after aortic valve replacement.

Timing of abnormal interventricular septal motion after cardiopulmonary bypass operations: Lack of injury proved by preoperative, intraoperative, and postoperative echocardiography

Abnormal interventricular septal motion after cardiopulmonary bypass is a widely known occurrence. The cause and exact timing of this phenomenon remain unclear. We have studied 21 patients prospectively with preoperative, intraoperative, and postoperative two-dimensional and M-mode echocardiograms. Intraoperative studies were obtained with the pericardium closed and open and after completion of procedures performed with cardiopulmonary bypass. Fourteen patients had coronary artery bypass graft operations alone. Six patients had valve replacement with or without coronary bypass, and one patient had removal of a left atrial myxoma. All patients had normal interventricular septal motion before the operation, and none had abnormal septal motion intraoperatively. Four to eight days postoperatively, the septum still thickened normally in all patients, with five patients having normal, nine patients abnormal, and seven patients paradoxical interventricular septal motion. Studies in 11 patients 1 to 4 months postoperatively showed no change from the early postoperative study. The pericardium was left open postoperatively in all patients. Six patients were studied a few hours after sternal closure and all had abnormal interventricular septal motion. We conclude that abnormal interventricular septal motion after cardiac operations is not due to injury of the septum, adhesion formation, or loss of pericardial constraint. Closure of the chest wall itself, with the pericardium left open, is associated with this abnormality.

Preservation of interventricular septal function in patients having coronary artery bypass grafts without cardiopulmonary bypass

Abnormal interventricular septal motion develops in the majority of patients after cardiac surgery and has been attributed to a variety of causes. This study assesses the role of cardiopulmonary (CP) bypass in the genesis of abnormal septal motion. Twenty-two patients having single coronary artery bypass grafts had septal motion and ejection fraction evaluated preoperatively and postoperatively. The results for 11 patients who had coronary artery bypass grafting (CABG) with CP were compared to those for 11 patients who had grafting without CP bypass. Postoperatively, all 11 patients having bypass grafting with CP bypass had diminution in septal function while 10 of 11 patients having bypass grafting performed without CP bypass had no change or improvement in septal motion ( p < 0.0005). Changes in ejection fraction were not statistically significantly different. This study suggests that abnormal septal motion in patients having CABG is related to CP bypass and/or myocardial preservation techniques.

Interventricular septal configuration as a predictor of right ventricular systolic hypertension in children: a cross-sectional echocardiographic study.

Abnormal interventricular septal position and motion have been noted in patients with right ventricular pressure overload. The quantitative relationship between this alteration in septal configuration and the severity of right ventricular systolic hypertension has not been previously reported. We used cross-sectional echocardiography to assess the radius of septal curvature at end-diastole, midsystole, and end-systole in 20 normal children and 29 children (ages 2 weeks to 20 years) undergoing cardiac catheterization for a variety of congenital cardiac disorders. The measured septal radius of curvature (r) was normalized by the ideal radius (ri) for the left ventricular cavity area and then expressed as normalized septal curvature [l/(r/ri)]. A slight leftward shift and flattening of the interventricular septum occurred in the course of normal systolic contraction (mean +/- SEM normalized curvature at end-diastole 0.92 +/- 0.03 and at end-systole 0.85 +/- 0.02; p less than .05). Marked exaggeration of this configurational change occurred in patients with right ventricular systolic hypertension (right ventricular systolic pressure greater than 50% systemic pressure), with progressive loss of curvature from end-diastole (0.45 +/- 0.05) to end-systole (0.19 +/- 0.06). Normalized septal curvature correlated well with relative right ventricular systolic pressure at all three sampling periods, with the best correlation at end-systole (r = .86). End-systolic flattening of the interventricular septum thus proved to be a sensitive marker for right ventricular systolic hypertension.

Echocardiography in chronic aortic insufficiency. Is valve replacement too late when left ventricular end-systolic dimension reaches 55 mm?

To determine whether a ventricular (LV) end-systolic dimension (ESD) greater than or equal to 55 mm and LV left fractional shortening less than 25% are risk factors for aortic valve replacement (AVR) in patients with aortic insufficiency, we analyzed the clinical course and M-mode echocardiograms in 47 consecutive patients who underwent AVR for isolated symptomatic AI. Group 1 patients (n = 27) had a preoperative ESD less than 55 mm (mean 44 mm, range 30-52 mm) and group 2 patients (n = 20) had a preoperative ESD greater than or equal to 55 mm (mean 62 mm, range 55-85 mm). One patient in group 1 and 10 patients in group 2 had left ventricular fractional shortening less than 25%. There were no perioperative or postoperative deaths during an average follow-up of 41 months (range 6-76 months). Five patients had perioperative myocardial infarctions (MIs), three in group 1 and two in group 2. Since myocardial protection with cold potassium cardioplegia was instituted, no patient has suffered a perioperative MI. The average preoperative New York Heart Association functional classification was 2.3 (group 1) and 2.6 (group 2). Postoperatively, it was 1.2 in group 1 and 1.1 in group 2. Thirty-three patients (20 in group 1 and 13 in group 2) had echocardiograms at least 1 year after AVR. Of these, LV-end diastolic dimension decreased fro 67 +/- 6 to 53 +/- 6 mm (mean +/- SD) in group 1 (p less than 0.001) and from 79 +/- 3 to 55 +/- 6 mm in group 2 (p less than 0.001). The LVESD also decreased, but this is difficult to interpret because of frequent postoperative abnormal interventricular septal motion. The LV cross-sectional area, an index of LV mass, decreased in group 1 from 25 +/- 5 to 20 +/- 5 cm2 (p lss than 0.001) and in group 2 from 32 +/- 9 to 20 +/- 5 cm2 (p less than 0.001). Postoperative end-diastolic dimension and cross-sectional area were not significantly different between the two groups. We concluded that in aortic insufficiency, a preoperative ESD greater than or equal to 55 mm does not preclude successful AVR, as judged by long-term survival, symptomatic relief, and normalization of LV dimensions assessed by echocardiography.

Mechanism of abnormal interventricular septal motion during delayed left ventricular activation.

To evaluate the mechanism of the abnormal motion of the interventricular septum (IVS) seen echocardiographically in some patients with relatively delayed ventricular activation, we simultaneously recorded high-fidelity left and right ventricular pressures and electrograms and echocardiograms of the IVS in nine open-chest dogs. During sinus rhythm and during left IVS pacing, the IVS was activated from left to right, preejection left ventricular pressure exceeded right ventricular pressure, and IVS motion was normal. During right ventricular pacing from the outflow tract, apex, free wall or right IVS was activated from right to left, right ventricular pressure increased before left ventricular pressure and simultaneously there was an abrupt posterior IVS motion. Simultaneous pacing from the right IVS and left ventricular free wall activated the IVS from right to left and produced a normal transseptal preejection pressure gradient and normal IVS motion. Simultaneous pacing from the left IVS and right ventricular free wall activated the IVS from left to right, and produced abrupt preejection posterior IVS motion coincident with an altered transseptal pressure gradient. During right ventricular pacing, IVS motion after the abrupt preejection posterior movement was variable. Anterior motion was associated with a greater asynchrony of right and left ventricular contraction than was normal posterior motion. We conclude that abrupt preejection posterior IVS motion seen with delayed left ventricular activation from right ventricular pacing is due to passive IVS displacement from an altered transseptal pressure gradient, and subsequent IVS motion depends on the degree of asynchrony between right and left ventricular contraction.