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Left ventricular function and coronary obstruction as predictors of survival following aorta-coronary bypass.

A retrospective analysis was undertaken of clinical data and catheterization studies of 151 consecutive unselected patients who underwent aorta-coronary bypass at the University of Kansas Medical Center between 1971 and 1973. The purpose was to determine the effect of preoperative left ventricular function and extent and severity of coronary artery obstruction on operative mortality rate and long-term survival. The postoperative follow-up period ranged from 10 to 49 months and averaged 26 months. Left ventricular function was assessed by qualitative analysis of left ventricular angiograms. Severity of coronary obstruction was quantified by scoring coronary arteriograms according to the system of Friesinger and associates. Patients with normal or near normal ventriculograms were considered to have good left ventricular function. Patients showing moderate or severe impairment of contraction were considered to have poor left ventricular function. Obstruction scores ranging from 2 to 7 points were classified as low scores, and scores from 8 to 15 points were classified as high scores. Four groups of patients were identified based upon preoperative left ventricular function and obstruction severity: Group I, 29 patients with good left ventricular function and low scores; Group II, 22 patients with poor left ventricular function and low scores. Group III, 28 patients with good left ventricular function and high scores. Elective aorta-coronary bypass in these three groups was accompanied by no operative or late deaths. Group IV comprised 72 patients with poor left ventricular function and high scores. In this group there was a 10 per cent operative mortality rate (7 of 72 patients) and a 5 per cent year late mortality rate. Relief of angina occurred equally in all groups. Thus operative risk can be prospectively determined by analysis of left ventricular function and severity of coronary obstruction. Surgical treatment resulted in negligible operative and late mortality rates (0 per cent) in all patients except those in whom poor ventricular function was accompanied by severe and diffuse coronary artery obstruction. Operation should be offered to this latter group (Group IV) despite the higher operative and postoperative risk because of salutary postoperative results.

Adult↗

Effects of rhythm regularization and rate control in improving left ventricular function in atrial fibrillation patients undergoing atrioventricular nodal ablation.

OBJECTIVES: To assess the relative contributions of rate control and rhythm regularization to left ventricular function in atrial fibrillation (AF) patients undergoing atrioventricular nodal ablation. This was performed by assessing the effect of ventricular rhythm regularization on left ventricular function during AF, and the effect of varying heart rate on left ventricular function after ablation. PATIENTS AND METHODS: Eleven patients with continuous AF and V/VI-R pacemakers undergoing therapeutic atrioventricular nodal ablation were studied. Preablation patients underwent two 30 min observation periods in a randomized, blinded fashion during which they were either in baseline AF (pacer set to default V/VI 50/min) or being paced using a rhythm stabilizing algorithm (RSA) designed to regularize rhythm without changing baseline ventricular rate. Six weeks after ablation, patients were again observed during the two following 30 min periods: pacing at a low clinically indicated rate (69+/-9 beats/min), and pacing at the rapid, mean preablation rate. During all observation periods, left ventricular function was measured continuously using a nuclear vest that provided validated measures of heart rate, ejection fraction, and normalized end-systolic volume (ESV) and end-diastolic (EDV) volume. RESULTS: Before ablation, RSA successfully regularized rhythm, decreasing the coefficient of variation of interbeat intervals 20+/-5% to 10+/-4% (P<0.001). The heart rate with RSA (105+/-19 beats/min) was not significantly different from the baseline AF rate (102+/-21 beats/min). Increased rhythm regularity achieved by RSA significantly improved left ventricular function, decreasing ESV from 62+/-12 units to 57+/-11 units (P=0.03), and increasing the ejection fraction from 31+/-11% to 36+/-11% (P=0.03). After ablation, at the clinically indicated low pacing rate of 69+/-9 beats/min, a much greater improvement in ejection fraction was observed, increasing to 44+/-13% (P=0.005 compared with preablation). However, rapid regular pacing at the mean preablation rate of 110+/-18 beats/min eradicated this improvement, decreasing the ejection fraction to 31+/-8% (P=0.003), and increasing ESV from 53+/-13 units to 62+/-8 units (P=0.006). CONCLUSIONS: Rhythm regularity achieved by a regularizing pacing algorithm can significantly, albeit modestly, improve left ventricular function in AF. However, more marked improvements in left ventricular function seen after ablation are primarily due to rate reduction alone.

Aged↗

Determinants of maximal right ventricular function.

After heart transplantation, right ventricular failure can occur because of increased afterload. Previous studies have suggested that the maximal pressure the right ventricle can develop is determined primarily by right ventricular perfusion pressure. However, the interaction of the left ventricle and the pericardium as functional co-determinants of maximal right ventricular function is unknown. This study was undertaken to determine the interaction of the pericardium, left ventricular pressure, and right coronary artery perfusion pressure as potential determinants of maximal right ventricular function. In an acute canine preparation, with progressive pulmonary artery constriction, maximal generated right ventricular pressure was determined over a range of left ventricular systolic pressures. Additional groups of dogs were studied with the right coronary artery cannulated and were maintained at constant perfusion pressure. In all preparations, the maximal pressure the right ventricle could generate was linearly related to left ventricular systolic pressure. Having a closed pericardium markedly enhanced this effect; some effect was present with an open pericardium, although the magnitude of the influence of left ventricular pressure on maximal right ventricular pressure was much less. Maintaining constancy of right coronary artery perfusion pressure, either at high or low values, did not alter these findings nor did it alter the influence of the pericardium. These results suggest that right ventricular perfusion may not be the sole determinant of maximal right ventricular function. Furthermore, with the pericardium open, such as in the posttransplantation state, the left ventricular contribution to maximal right ventricular function may be diminished, increasing vulnerability for right ventricular failure caused by increased afterload.

Animals↗

Improved left ventricular function after renal transplantation.

Patients with severely impaired left ventricular function are known to have a poor prognosis. We describe a 20-year-old man with end-stage renal failure, on dialysis, with severely impaired left ventricular function which dramatically improved after renal transplantation. This suggests that poor left ventricular function need not preclude renal transplantation and may, in fact, offer an alternative to combined renal and cardiac transplantation.

Adult↗

Prediction of global left ventricular function after bypass surgery in patients with severe left ventricular dysfunction. Impact of pre-operative myocardial function, perfusion, and metabolism.

AIMS: Previous studies have compared the accuracy of various tests of viability for the prediction of recovery of regional left ventricular function; global left ventricular recovery has been less well studied, although it has important prognostic and functional ramifications. We sought to identify the relative contribution of ischaemia, regional and global contractile reserve, perfusion and metabolic function to changes in left ventricular volumes and global function after coronary artery bypass surgery in patients with severe left ventricular dysfunction. METHODS AND RESULTS: Dipyridamole stress Rb-82, fluorodeoxyglucose positron emission tomography and low and high-dose dobutamine-atropine stress echocardiography were obtained in 66 patients with left ventricular impairment. Myocardial segments were considered viable if ischaemia or either metabolic or contractile reserve were present, on positron emission tomography or dobutamine echocardiography. Resting left ventricular function was reassessed after surgery (mean 10+/-3 weeks) in the 59 patients who had not suffered a major peri-operative event; functional improvement was defined by a 5% increment of ejection fraction. Myocardial viability was found in 37 (63%) patients using positron emission tomography and in 42 (71%) patients using dobutamine echocardiography; post-operative functional improvement was noted in 28 (47%) patients. In univariate analyses, predictors of global post-operative functional recovery included: the extent of viability according to positron emission tomography [OR (odds ratio): 2.08 for each additional viable segment, 95% CI (confidence interval): 1.33-3. 25, P=0.001] or dobutamine echocardiography (OR: 2.06 for each additional viable segment, 95% CI: 1.28-3.30, P=0.003) and the increase in ejection fraction with low-dose dobutamine (OR: 1.9 for each 1% increase in ejection fraction with low dose dobutamine, 95% CI 1.39-2.61, P<0.0001). In a multivariate model which included evidence of viability by either technique, and change in ejection fraction with low-dose dobutamine echocardiography, only change in ejection fraction with low-dose dobutamine echocardiography was predictive of post-operative left ventricular functional recovery (adjusted OR: 1.81, 95% CI: 1.30-2.52, P=0.0005). CONCLUSION: Among patients with severe left ventricular dysfunction who are referred for surgical revascularization, the overall accuracies of positron emission tomography and dobutamine echocardiography for the prediction of post-operative myocardial recovery are comparable. However, the strongest predictor of overall improvement of post-operative left ventricular function is an increase of ejection fraction with a low-dose dobutamine infusion.

Aged↗

Radionuclide assessment of ventricular function and risk stratification after myocardial infarction.

Prognosis after acute myocardial infarction is determined primarily by left ventricular function and by the extent to which additional coronary obstructions jeopardize viable myocardium. Radionuclide ventriculography is well suited for noninvasive assessments of resting and exercise ventricular function after acute myocardial infarction. The prognostic importance of resting left ventricular function after acute myocardial infarction is well established. Several studies have reported the prognostic utility of submaximal exercise radionuclide ventriculography at the time of hospital discharge. Patients with globally depressed left ventricular function after acute myocardial infarction are at increased risk for cardiac death, while patients with normal resting ventricular function but abnormal function during exercise appear to be at risk for nonfatal ischemic events. The development of gated tomographic techniques and new radiopharmaceuticals will make available more accurate and detailed assessments of ventricular function and combined assessments of function and perfusion. These new developments require further investigation but appear to be promising new techniques with the potential for providing improved assessments of prognosis after acute myocardial infarction.

Cardiac Volume↗

Coronary angioplasty after intravenous streptokinase in acute myocardial infarction: influence of restenosis on clinical outcome and left ventricular function.

The importance of recurrence of stenosis on clinical outcome and left ventricular function was studied in a consecutive series of patients with acute evolving myocardial infarction (maximal duration of pain 4 h) and thrombolysis (1.5 x 10(6) units of streptokinase intravenously over 60 min) with recanalized single-vessel disease and subsequent successful coronary angioplasty. Coronary angioplasty was performed in 76 patients between 24 hours and 8 days (mean interval 3.3 days) after thrombolysis and was successful in 86% (65/76). The in-hospital reinfarction rate was 5.2% (2 acute and 2 in-hospital reinfarctions). Repeat angiography after a mean interval of 5.9 months revealed a 39% (24/62) restenosis rate (21 restenoses, 3 reocclusions). Restenoses were associated with significantly more clinical complaints (21% vs. 62%; p less than 0.001). Left ventricular function analysis showed significant improvement in the mean global ejection fraction (6.6 +/- 6.0%; p less than 0.001) and mean regional wall motion of the infarct zone (6.2 +/- 8.2%; p less than 0.01) only in patients without restenosis. Recovery of left ventricular function was more evident in inferior than in anterior wall infarctions. In contrast, patients with restenosis had no change in left ventricular function. Thus, the present study demonstrates the adverse influence of restenosis on recovery of left ventricular function and clinical outcome.

Angioplasty, Balloon, Coronary↗

Heat shock protein 70 gene transfection protects mitochondrial and ventricular function against ischemia-reperfusion injury.

BACKGROUND: Upregulation of heat shock protein 70 (HSP70) is beneficial in cardioprotection against ischemia-reperfusion injury, but the mechanism of action is unclear. We studied the role of HSP70 overexpression through gene therapy on mitochondrial function and ventricular recovery in a protocol that mimics clinical donor heart preservation. METHODS AND RESULTS: Hemagglutinating virus of Japan (HVJ)-liposome technique was used to transfect isolated rat hearts via intracoronary infusion of either the HSP70 gene (HSP group, n=16) or no gene (CON group, n=16), which was heterotopically transplanted into recipient rats. Four days after surgery, hearts were either perfused on a Langendorff apparatus for 30 minutes at 37 degrees C (preischemia studies [n=8/group]) or perfused for 30 minutes at 37 degrees C, cardioplegically arrested for 4 hours at 4 degrees C, and reperfused for 30 minutes at 37 degrees C (postischemia studies [n=8/group]). Western blotting and immunohistochemistry confirmed HSP70 upregulation in the HSP group. Postischemic mitochondrial respiratory control indices (RCIs) were significantly better preserved in HSP than in CON hearts: NAD(+)-linked RCI values were 9.54+/-1.1 versus 10.62+/-0.46 before ischemia (NS) but 7.98+/-0.69 versus 1.28+/-0.15 after ischemia (P<0.05), and FAD-linked RCI values were 6.87+/-0.88 versus 6.73+/-0.93 before ischemia (NS) but 4.26+/-0.41 versus 1.34+/-0.13 after ischemia (P<0.05). Postischemic recovery of mechanical function was greater in HSP than in CON hearts: left ventricular developed pressure recovery was 72.4+/-6.4% versus 59.7+/-5.3% (P<0.05), maximum dP/dt recovery was 77.9+/-6.6% versus 52.3+/-5.2% (P<0.05), and minimum dP/dt recovery was 72.4+/-7.2% versus 54.8+/-6.9% (P<0.05). Creatine kinase release in coronary effluent after reperfusion was 0.20+/-0.04 versus 0.34+/-0.06 IU. min(-1). g wet wt(-1) (P<0.05) in HSP versus in CON hearts. CONCLUSIONS: HSP70 upregulation protects mitochondrial function after ischemia-reperfusion injury; this was associated with improved preservation of ventricular function. Protection of mitochondrial function may be important in the development of future cardioprotective strategies.

Animals↗

Global and regional right ventricular function after acute myocardial infarction: dependence upon site of left ventricular infarction.

The relation of global and regional right and left ventricular function during the acute phase after a first myocardial infarction was assessed by first pass radionuclide angiography in 20 patients (10 after anterior and 10 after inferior myocardial infarction). The right ventricular ejection fraction did not differ significantly between the groups, but left ventricular ejection fraction was significantly depressed after anterior myocardial infarction. There was evidence of right ventricular dilatation and impaired transit in the group with inferior infarction. Five patients with anterior infarction and six with inferior infarction had abnormal right ventricular ejection fractions. Right ventricular wall motion abnormalities affected the septal wall in the group with anterior infarction and the free wall in the group with inferior infarction. The relation between right and left ventricular ejection fractions was markedly different in the two groups. In the group with anterior infarction there was a significant linear relation between right and left ventricular ejection fraction, whereas in the group with inferior infarction there was not. Thus right ventricular dysfunction commonly occurs after both anterior and inferior myocardial infarction. Right and left ventricular impairment are related after anterior myocardial infarction, but are independent after inferior myocardial infarction. Finally, the different effects of anterior and inferior myocardial infarction on right ventricular function may be explained by differences in septal and free wall involvement.

Adult↗

Ventricular function in Chagas' heart disease.

Invasive and noninvasive methods used to evaluate ventricular function in Chagas's disease are reviewed. The traditional indices of overall ventricular performance reflect the interaction of preload, contractility, afterload and heart rate. Therefore, they are unable to distinguish changes in contractility from modifications of loading conditions. The role of ventricular function as a predictor of mortality in chronic Chagas' heart disease is discussed. Ventricular function abnormalities in patients with indeterminate and digestive forms of Chagas' disease are especially emphasized. Finally, the evidence of early impairment of diastolic performance in digestive forms of Chagas' disease are especially emphasized. Finally, the evidence of early impairment of diastolic performance in patients with Chagas' disease is presented.

Chagas Cardiomyopathy↗

[Effect of aortocoronary bypass surgery on left ventricular function and coronary sinus blood flow in patients with severe left ventricular dysfunction].

Left ventricular function and coronary sinus blood flow were evaluated in 7 patients with severe left ventricular dysfunction at rest before and after aortocoronary bypass surgery, and during exercise after surgery. Same evaluations were performed in 8 normal subject (G-C). Cardiac index (CI) at rest (2.09 +/- 0.55 l/min/m2) significantly increased after operation (2.94 +/- 0.59 l/min/m2) (p less than 0.02). There was no difference between CI during exercise after operation (5.94 +/- 1.51 l/min/m2) and that in G-C. Left ventricular end-diastolic pressure (LVEDP) at rest before operation (16 +/- 8 mmHg) was significantly higher than that in G-C (p less than 0.05). This difference disappeared after operation. LVEDP during exercise after operation (25 +/- 10 mmHg) was significantly higher than that in G-C (p less than 0.01). Coronary sinus blood flow (CSF) at rest (73 +/- 15 ml/min) significantly increased after operation (123 +/- 44 ml/min) (p less than 0.02). There was no difference between CSF during exercise after operation (282 +/- 99 ml/min) and that in G-C. These data indicated that the aortocoronary bypass surgery was effective on left ventricular function and coronary sinus blood flow in patients with severe left ventricular dysfunction.

Adult↗

[Left ventricular function in adult patients after the atrial switch operation for transposition of the great arteries].

OBJECTIVES: Right ventricular function may deteriorate after the atrial switch operation in patients with transposition of the great arteries, but the effect on left ventricular function is unknown. Chronic left ventricular function was evaluated in adult patients after the atrial switch operation for transposition of the great arteries. METHODS: Right and left ventricular functions were evaluated using data from cardiac catheterization performed in nine patients older than 17 years who had undergone the atrial switch operation for transposition of the great arteries. The mean age at operation was 19 +/- 16 months and the age at catheterization ranged from 17 to 32 years (mean age 23 +/- 5 years). Echocardiography was performed in all patients to evaluate tricuspid regurgitation. Myocardial perfusion studies using technetium-99 m-tetrofosmin were assessed in five patients. RESULTS: Mean right ventricular end-diastolic volume was slightly increased to 122 +/- 27% of the normal value and mean right ventricular ejection fraction was depressed to 44 +/- 5% of the normal value. Left ventricular ejection fraction ranged from 37% to 63% (mean 50 +/- 7%) and was under 50% in four of the nine (44%) patients. Right ventricular ejection fraction was positively correlated with left ventricular ejection fraction(r = 0.72, p < 0.05). All patients had tricuspid regurgitation, mild in four, moderate in four, and severe in one patient. Left ventricular ejection fraction was lower in patients with moderate or severe tricuspid regurgitation(54 +/- 4%) than in patients with mild tricuspid regurgitation(47 +/- 6%, p < 0.05). Mild or moderate perfusion abnormalities were observed in all patients (five of five) who underwent myocardial perfusion studies. Mean right and left ventricular ejection fractions were 43 +/- 3% and 50 +/- 3%, respectively, in patients who underwent myocardial perfusion study, which were under the normal levels. CONCLUSIONS: Left ventricular dysfunction is common in adult patients after the atrial switch operation for transposition of the great arteries. Some right ventricular abnormalities may correlate with the left ventricular dysfunction.

Adolescent↗

Comparison of multigated radionuclide angiography with ultrasonic sonomicrometry over a wide range of ventricular function in the conscious dog.

This study compared the noninvasive assessment of left ventricular function with radionuclide angiography with that obtained with ultrasonic sonomicrometry. Left ventricular ejection fraction and rate of ventricular ejection (dV/dt) were measured with both techniques over a wide range of ventricular function. Six dogs were prepared with epicardial crystals across the major and minor axes of the left ventricle, paired transmural wall thickness crystals and a left ventricular catheter. The animals were studied while awake after they had recovered from operation. Left ventricular volume was calculated from the ultrasonic sonomicrometric dimension measurements and the equation for a prolate ellipsoid; dV/dt was calculated from the stroke volume and ejection time. Radionuclide angiograms were performed using technetium-99m--labeled red blood cells and an Anger camera with a converging collimator interfaced to a computer programmed for multigated acquisition. A wide range of ventricular function was produced with sequential infusion of isoproterenol, propranolol, phenylephrine and sodium thiamylal. Ejection fraction and dV/dt were measured simultaneously during each intervention using the time-activity curves of the multigated radionuclide angiogram and ultrasonic sonomicrometric dimensions. Regression analyses demonstrated a close correlation between the simultaneous measurements of ejection fraction (r values ranged from 0.95 to 0.99) and dV/dt (r values ranged from 0.87 to 0.99). These data indicate that noninvasive multigated radionuclide angiography accurately assesses changes in ejection fraction and dV/dt over a wide range of ventricular function.

Animals↗

Longitudinal left ventricular function in a population of healthy adults: a tissue Doppler imaging study.

BACKGROUND: Longitudinal left ventricular function is a major determinant of global ventricular function and is probably more sensitive than radial function in the detection of disease. Tissue Doppler imaging of the mitral annulus allows the study of longitudinal left ventricular function. METHODS: Forty-five healthy volunteers divided into two groups (younger and older than 45 years) were studied with pulsed tissue Doppler imaging of the 4 sides of the mitral annulus (septal, lateral, inferior, anterior) in 4 and 2 apical chamber views. In each wave (systolic-s, rapid filling-e, atrial contraction-a) we analyzed velocities, time intervals and velocity-time integrals, as well as heterogeneity and asynchrony indexes. Data were compared between the different sides in each group, between groups and with conventional Doppler data. RESULTS: In contrast to the septal side, the lateral side of the annulus shows higher velocities and velocity-time integrals of the s and e waves, with non-significantly shorter isovolumic relaxation time and shorter time to peak e. There is functional agreement between the lateral and inferior sides versus the septal and anterior sides of the annulus. Most systolic parameters remained unchanged with aging; however, aging was associated with decreased e velocity, increased a velocity and inverted e/a ratio. The relation between s and fractional shortening also did not change with aging. Annular isovolumic contraction time and isovolumic relaxation time were shorter than their respective global time intervals. CONCLUSIONS: This study shows that there are physiological differences in velocities, time intervals and velocity-time integrals between the 4 sides of the mitral annulus, reflecting physiological heterogeneity and asynchrony, and that some of these parameters are age dependent. These data also contribute to a better understanding of longitudinal left ventricular function and may be useful in future studies as reference values in control groups.

Adult↗

The use of gated radionuclide ventriculography as a noninvasive method of evaluating right ventricular function in dogs with experimentally induced congestive heart failure.

Gated radionuclide ventriculography was evaluated as a noninvasive method of quantifying right ventricular function in dogs with experimentally induced congestive heart failure. Gated radionuclide ventriculography measurements of right ventricular function (right ventricular ejection fraction, right ventricular average emptying rate, and right ventricular average filling rate) were related to standard hemodynamic and echocardiographic measurements. Congestive heart failure was induced by rapid ventricular pacing in eight normal dogs. Hemodynamic, echocardiographic, and gated radionuclide ventriculography measurements were obtained before and after development of biventricular failure. Congestive heart failure resulted in significant changes in all hemodynamic, echocardiographic, and gated radionuclide ventriculography measurements with the exception of systemic arterial pressure. Right ventricular ejection fraction was inversely related to pulmonary artery systolic, diastolic, and mean pressure, and right ventricular average emptying rate was inversely related to the pulmonary artery systolic, diastolic, and mean pressure. Right ventricular ejection fraction was inversely related to left ventricular filling pressure, (pulmonary capillary wedge pressure). Neither the echocardiographic measurements of right ventricular size (right ventricular internal diastolic dimension) nor the right ventricular end-diastolic pressure were related to right ventricular ejection fraction and right ventricular average emptying rate. However, echocardiographic measurements of right ventricular dimension were related to right ventricular filling pressure. The gated radionuclide ventriculography indexes of right ventricular function, right ventricular ejection fraction and right ventricular average emptying rate, are affected by afterload but unaffected by preload, whereas the echocardiographic measurement of right ventricular dimension is related to preload. Gated radionuclide ventriculography provides right ventricular data which is unique from that obtained by standard echocardiographic imaging. Also, gated radionuclide ventriculography has potential value as a noninvasive means of estimating a change in pulmonary artery pressure.

Animals↗

[Left ventricular function in chronic obstructive lung disease (author's transl)].

Left ventricular function was studied at rest and during post-extrasystolic potentiation in 18 patients with chronic obstructive lung disease. The contractility indices used were obtained from pressures recorded in the isovolumetric period (left ventricular end-diastolic pressure, Vmax., VECmax., dP/dtmax.) and from volume variations during ejection (end-diastolic volume, ejection fraction, VCF). Left ventricular diastolic compliance was also evaluated. All patients were hypoxic (PaO2 = 58 +/- 7 torr); six of them had cor pulmonale (group B); the remaining 12 patients constituted group A. Left ventricular function of groups A and B was similar; we conclude that right cardiac failure, in cor pulmonale, is not secondary to left ventricular failure. However, left ventricular dysfunction exists; the left ventricle is hypertrophied (probably resulting from chronic hypoxia). Pump function is altered (abnormal ventricular function points are found), but left ventricular kinetics is normal or exaggerated (ejection fraction and VCF are increased). Isovolumetric phase contractility indices are diminished; however, they may increase normally during post-extrasystolic potentiation. Left ventricular compliance is abnormal due to left and right ventricular hypertrophy and to paradoxical movement of the interventricular septum which impedes diastolic expansion of the left ventricle. These changes are responsible for decreased left ventricular output. There seems to exist an impairment of left ventricular function related to both intrinsic (secondary to hypoxia, hypercapnia, left ventricular hypertrophy) and extrinsic factors (right ventricula hypertrophy deviating interventricular septum, lowering of left ventricular preload).

Adult↗

Effects of dynamic cardiomyoplasty on right ventricular function.

This study was planned to document the right ventricular function immediately after cardiomyoplasty. Right ventricular volumes were calculated with the use of fast response thermistor. Right ventricular end-diastolic volume was reduced from 91 +/- 8 mL/M2 to 75 +/- 7 mL/M2 (p < 0.05) and right ventricular end-systolic volumes increased from 51 +/- 5 mL/M2 to 59 +/- 4 mL/M2 24 hours after the operation. Central venous pressure was raised from 2 +/- 1 to 9 +/- 3 mm H2O. These changes were interpreted as impairment of the right ventricular diastolic function. Cardiac index raised from 1.8 +/- 0.5 L/M2 per minute to 2.7 +/- 0.3 L/m2 per minute within a period of 7 days (p < 0.05). As a result of this study, we concluded that preoperatively normal right ventricular function deteriorates after the cardiomyoplasty. In the intensive care unit volume balance must be carefully monitored to avoid creating right ventricular dysfunction.

Adult↗