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In patients with depressed left ventricular function, the normal precautions during transesophageal atrial pacing may not be sufficient to prevent life threatening arrhythmias. In this article two cases of ventricular fibrillation induced during this technique, aimed at treating atrial flutter, are described.
We studied the global and regional left ventricular function, its determinants and its modification with time, in orthotopic heart transplant recipients. We reviewed the left ventricular cineangiography performed 1 (50 patients), 2 (33 patients), 3 (18 patients), and 4 (seven patients) years after operation. Regional wall motion was quantitatively evaluated by the area method. All patients had angiographically normal coronary arteries and no evidence of acute rejection at the time of the study. One year after heart transplantation, cardiac index and left ventricular ejection fraction were mildly but significantly lower than normal. Cardiac index was more than 2.5 L/min/m2 in all but one patient, and ejection fraction was more than 50% in all patients. Only previous acute cardiac rejection necessitating therapy and arterial hypertension showed some influence on the left ventricular function. Two years after operation, the left ventricular end-diastolic volume was increased, and left ventricular mass-volume ratio decreased compared with year 1. Three years after operation, an increase of left ventricular end-diastolic pressure and of left ventricular ejection fraction was also evident. Four years after operation, the heart rate was higher, compared with previous years. Even if the changes in the parameters of left ventricular function were significant, they were small in terms of absolute value. Regional hypokinesia was detected 1 year after heart transplantation in eight patients, involving one segment in six patients and two segments in two patients.(ABSTRACT TRUNCATED AT 250 WORDS)
BACKGROUND: We hypothesized that left ventricular function could be improved with cardiomyoplasty using the right latissimus dorsi. METHODS AND RESULTS: Five dogs underwent cardiomyoplasty using the right latissimus dorsi. Left ventricular volume and pressure were measured using sonomicrometry and a micromanometer catheter, respectively. Pressure volume loops were recorded with the muscle stimulated at 1:2 and with transient caval occlusion. During stimulated beats, there were significant increases in stroke work (13.90 +/- 4.49 vs 9.78 +/- 3.81 g/m, P < .01), preload recruitable stroke work (0.766 +/- 0.110 vs 0.594 +/- 0.207 g.m-1 x m-3, P < .05), and stroke volume (15 +/- 4 vs 10 +/- 3 mL, P < .05) when compared with unstimulated beats. There were no changes in diastolic filling. This operation was done in 11 patients, with no operative deaths. Six weeks after surgery, resting left ventricular ejection fraction (LVEF) increased from 25 +/- 1.6% to 35 +/- 3% (P < .05), and left ventricular end-diastolic volume (LVEDV) decreased from 365 +/- 18 to 307 +/- 24 mL, (P < .05). Nine patients were alive at 6 months. Preoperative and 6-month LVEF and LVEDV for those 9 patients were 26 +/- 2% and 29 +/- 2% (P = NS) and 316 +/- 23 and 261 +/- 22 mL (P < .05), respectively. CONCLUSIONS: Long-term studies are needed to determine if these changes will improve patient survival.
INTRODUCTION: Surgical restoration of the left ventricular wall (Dor procedure) has been advocated as a therapy for left ventricular dysfunction due to ischemic cardiomyopathy. This procedure involves placement of an endoventricular patch through a ventriculotomy. METHODS: We reviewed our series of patients that underwent the Dor procedure within the past 4 years and examined their pre and postoperative ventricular function and mitral valve function. Pre and postoperative ejection fraction and degree of mitral regurgitation were analyzed using the paired Student t-test. We hypothesized that this procedure would result in improved ventricular function and that it would also help improve mitral valve function. RESULTS: Thirty-four patients underwent this procedure, with one death. Of these, 30 patients underwent concomitant coronary artery bypass grafting and 8 patients had mitral intervention (seven had an Alfieri repair of the mitral valve, and one had mitral valve annuloplasty). The average preoperative ejection fraction among these patients was 26.8% (range 10-45%). The postoperative ejection fraction was significantly higher at 35.4% (range 25-52%) (P <.001). We noted an improvement in ejection fraction in 27 patients (82%). We also noted that 21 of 33 patients (64%) had improvement in the degree of mitral regurgitation based on echocardiography data (P <.001). CONCLUSIONS: We conclude that the Dor procedure results in improvement in the left ventricular function. Furthermore, we also note that this procedure ameliorates mitral regurgitation in a majority of these patients even in the absence of associated mitral valve procedures, probably due to reduction in the size of the ventricle and improved orientation of the papillary muscles.
The effect of preoperative left ventricular function on eraly and late prognosis was assessed in 69 patients with aortic regurgitation who underwent homograft replacement of the aortic valve. Patients were divided into two groups: Group A (38 patients) had an ejection fraction of 0.46 or more and Group B (31 patients) had an ejection fraction of 0.45 or less. Clinical data, hemodynamic data, and operative results were compared in the two groups. In Group A there was one early death (2.6%) and there were two late deaths (5.3%) compared to two early deaths (6.5%) and seven late deaths (22.6%) in Group B during a follow-up period of 13 to 98 months (mean, 49 months). Actuarial analysis showed a 94% survival at 6 years in Group A compared to 80% in Group B. Twenty-four patients were reinvestigated by repeat cardiac catheterization and coronary angiography at a mean time of 38 months following valve replacement. Left ventricular function was assessed by computerized quantitative radial analysis of segmental wall motion. Improvement in left ventricular function occurred in eight of the 14 patients reinvestigated in Group B, and appeared to be closely related to the etiology of the initial valve lesion. Despite the higher mortality rate in patients with poor left ventricular function, most derived considerable benefit from operation.
OBJECTIVES: This study was designed to assess the predictive value of myocardial viability diagnosed by dobutamine transesophageal echocardiography and fluorine (F)-18 fluorodeoxyglucose positron emission tomography for left ventricular functional recovery after revascularization in patients with chronic left ventricular dysfunction. BACKGROUND: The identification of akinetic but viable myocardium is of particular importance for the selection of patients with a compromised left ventricle who will benefit from coronary revascularization. METHODS: Multiplane rest and dobutamine transesophageal echocardiography (dobutamine, 5 and 10 microg/min per kg) studies and F-18 fluorodeoxyglucose positron emission tomographic studies at rest were performed in 2 patients with 1) previous myocardial infarction and regional akinesia, 2) a stenosed infarct-related coronary artery, and 3) a patent infarct-related vessel after revascularization. A basally akinetic segment was considered viable by transesophageal echocardiography if dobutamine-induced contractile reserve could be observed. Viability by positron emission tomography was defined as F-18 fluorodeoxyglucose uptake > or = 50% of the maximal uptake in a region with normal wall motion. Recovery of regional left ventricular function 4 to 6 months after revascularization was diagnosed by transesophageal echocardiography if > or = 50% of segments akinetic at baseline had improved wall thickening. RESULTS: Dobutamine transesophageal echocardiography identified viable infarct regions in 25 (59%) of 42 patients, and F-18 fluorodeoxyglucose positron emission tomography in 30 (71%) of 42 patients, yielding diagnostic agreement in 86% of patients. Sensitivity and specificity for prediction of left ventricular functional recovery in individual patients was 92% and 88%, respectively, for dobutamine transesophageal echocardiography versus 96% and 69% for F-18 fluorodeoxyglucose positron emission tomography. Segments remaining akinetic after revascularization had a significantly lower (p < 0.001) F-18 fluorodeoxyglucose uptake (48 +/- 15%) than that (73 +/- 15%) of segments with recovery of regional left ventricular function. CONCLUSIONS: Both dobutamine transesophageal echocardiography and F-18 fluorodeoxyglucose positron emission tomography were highly sensitive in predicting functional recovery of chronically kinetic or dyskinetic myocardium after successful revascularization. Thus, dobutamine transesophageal echocardiography is a clinically valuable alternative to F-18 fluorodeoxyglucose positron emission tomography for assessing residual viability and predicting functional recovery after revascularization.
Left-ventricular function was assessed by sectional echocardiography in 250 patients with unstable angina on admission; the test was repeated after medication-produced-stabilization in 130 and after aorto-coronary shunting in 50 of those. Total and/or regional left-ventricular contractility disorders were detected in 82.4%, depending on the type and severity of coronary bed affection as well as the presence and magnitude of postinfarction cardiosclerosis. The nitroglycerin test improved left-ventricular function in 83% of cases where it was initially depressed. Left-ventricular function was improved after medication in 79% of patients and after surgery in 60%. Total left-ventricular ejection fraction increased by an average of 11.2 +/- 1.5%, whereas the ejection fraction of segments, connected with the shunted-artery blood supply network, increased by 19.5 +/- 2.3% (p less than 0.01). The efficiency of pharmacological treatment depended on the number of affected coronary arteries and the presence and severity of postinfarction cardiosclerosis, while surgical treatment also depended on the extent of myocardial revascularization for its efficiency.
Evidence exists that left ventricular function is impaired in chronic uremic patients. During hemodialysis (HD) treatment, myocardium undergoes electrolyte, hemodynamic and neuro-humoral stress; however, data about the acute changes on ventricular function are controversial. Aim of the present study was to evaluate the effect of a single hemodialysis session on left ventricular (LV) systolic and diastolic function using pulsed tissue Doppler imaging (TDI) sampled by echocardiography. The study group included 20 uremic patients (17 males, aged 51+/-13 yrs) on maintenance HD, free from clinically overt cardiac dysfunction who underwent echocardiography with pulsed TDI 30 min prior and 30 min after a HD session. TDI was performed by placing the sample volume in the center of the basal lateral segment and the basal interventricular septum in the apical four-chamber view. Myocardial systolic wave (S(m)) and early (E(m)) and atrial (A(m)) diastolic waves were measured. On standard sonography examination, no significant changes in LV systolic function parameters were observed after HD, but the indices for LV diastolic function deteriorated significantly (peak E, 75.4+/-11.2 vs. 58.8+/-12.5 cm/s, P<0.01; E/A ratio, 1.0+/-0.3 vs. 0.8+/-0.2, P<0.01). However, regarding TDI measures following HD, the patients exhibited a lower S(m) peak (septum: 7.6+/-1.1 vs. 5.9+/-0.8 cm/s; lateral wall: 7.7+/-1.7 vs. 6.8+/-1.2 cm/s, P<0.001), a lower E(m) peak (septum: 8.3+/-1.6 vs. 6.3+/-1.7 cm/s; lateral wall: 10.2+/-2.4 vs. 7.1+/-1.9 cm/s, P<0.001), and a reduced E(m)/A(m) ratio (septum: 1.0+/-0.4 vs. 0.7+/-0.2; lateral wall: 1.2+/-0.5 vs. 0.7+/-0.2, P<0.001, respectively), as compared to pre-HD parameters. Of interest, peak E(m), and E(m)/A(m) ratio of the lateral wall were negatively related to ultrafiltration rate (r = -0.60, P<0.05 and -0.69, P<0.01, respectively). Our data indicate that a single hemodialysis session is associated with acute deterioration of diastolic and systolic parameters of myocardial function, as assessed by TDI. These reversible changes could be considered as a cardiac stunning that seems to be related to the ultrafiltration rate and then to the interdialysis weight gain. These findings suggest that low ultrafiltration volume and/or limited interdialytic weight gain are cardioprotective measures in hemodialysis patients.
OBJECTIVE: Assessment of ventricular function in the fetus has been limited for many reasons, including relative cardiac size and atypical orientation of fetal cardiac structures. A myocardial performance index (MPI) has been described in adult and pediatric populations as an echocardiographic measure of global (systolic and diastolic) ventricular performance. Because the MPI is a Doppler index, it is independent of ventricular geometry and can be applied to both left and right ventricular function. This study attempts to define the MPI in a group of normal fetuses and compare these data to other published studies of this index. STUDY DESIGN: The right ventricular (RV) and left ventricular (LV) MPI were measured in 125 normal fetuses (20--40 weeks gestation, mean age 28 weeks). These fetuses were divided into five gestational age groups for comparison. These data were compared to 152 normal children (age 3--18 years, mean age 9.3 years). RESULTS: In normal fetuses, the LV MPI was 0.36 +/- 0.06 and the RV MPI was 0.35 +/- 0.05. This was not statistically different from the group of normal children in whom the LV MPI was 0.35 +/- 0.03 and the RV MPI was 0.32 +/- 0.03. In addition, no significant change in the fetal MPI was seen with advancing gestational age. CONCLUSION: This study demonstrates that fetal ventricular function can be quantitatively measured with the MPI. The MPI provides an easily obtainable and reproducible measure of fetal ventricular performance that can be readily incorporated into all fetal echocardiographic examinations.
Left ventricular systolic function was assessed by radionuclide angiography in 107 consecutive transplant recipients who were alive one year after operation. Mean (SEM) ejection fraction was 62.4 (4.6) at rest and 68.8 (5.4) on exercise. The influence of donor-related factors (donor age and sex, ischaemia time), recipient-related factors (recipient age and sex, frequency of acute rejection), type of immunosuppression (cyclosporin/azathioprine or prednisolone/azathioprine), and frequency of hypertension on left ventricular function one year after operation was examined by univariate and multivariate analysis. There was a close association both at rest and on exercise between a higher ejection fraction and treatment with cyclosporin/azathioprine. There was a trend for lower donor and recipient age, shorter ischaemia time, and fewer rejection episodes to be associated with better left ventricular function, but this was not statistically significant. Left ventricular systolic function was well maintained in most patients a year after cardiac transplantation. The type of immunosuppression used had a strong influence on the left ventricular systolic function of the transplanted heart.
Preoperative and postoperative left ventricular cineangiograms of 26 patients with mitral stenosis (MS) were analyzed to calculate left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and systolic regional wall motion. Nine patients underwent commissurotomy (OMC group) and 17 patients underwent mitral valve replacement (MVR group). In both groups, postoperative EDV, SV and EF tended to increase, while ESV remained unchanged. In the OMC group, systolic wall motion of the left ventricle was found to be improved postoperatively, whereas systolic wall motion in the MVR group was found to be impaired postoperatively. The latter finding was assumed to be due to excision of the papillary muscles and chordae tendineae. Preservation of these structures is likely to be important for better postoperative functional recovery of the left ventricle.
The evolutionary changes in left ventricular function induced by cold pressor stimulation were investigated at 90 second intervals by rapid sequential first pass radionuclide angiography using the short half life tracer gold 195m. The results in 12 subjects with normal coronary arteries were compared with those in 12 patients with coronary artery disease. Left ventricular ejection fraction fell significantly from resting values in both groups after 1 minute of cold pressor, but only in patients with coronary disease was the significant fall maintained at 2.5 and 4 minutes. In both groups, the maximum decrease in ejection fraction occurred after 1 minute, whereas the maximum rise in systolic blood pressure occurred after 2.5 minutes. New abnormalities of regional ventricular function developed in 10 normal subjects after 1 minute of cold, with a total of 12 new abnormal segments. Only two such segments were seen at the later stages of imaging. Twenty one new segments developed after 1 minute in the coronary disease group, and 13 segments remained abnormal after 4 minutes. Three patients, two of whom had left main stem stenoses, showed persistent abnormalities of ventricular function after 2 minutes of recovery from cold stimulation. Thus left ventricular function changes rapidly during a period of cold stimulation in both those without and those with coronary disease. When the cold pressor test is used with multiple gated equilibrium imaging, the timing of imaging may be crucial to the results and interpretation of the test. The discordance between functional changes and rise in blood pressure is further evidence that alterations in afterload are not solely responsible for cold induced abnormalities.
Ventricular function may improve after coronary artery bypass grafting (CABG) in patients with ischemic cardiomyopathy depending on the amount of contractile myocardial reserve. Based on the studies using dobutamine echocardiography to predict regional wall improvement after revascularization, we investigated the benefit of low-dose dobutamine radionuclide ventriculography for assessing functional contractile reserve in this population. The study group included 56 patients with ischemic cardiomyopathy (mean left ventricular [LV] ejection fraction [EF] of 23 +/- 5%) and multivessel disease, who were referred for viability assessment. All underwent radionuclide ventriculography before and during infusion of 5 and 10 microg/kg/min of dobutamine. An increase in global LVEF from rest to dobutamine was calculated, and 10% was considered the cutoff value to predict ventricular improvement after CABG. Of the 35 patients who underwent CABG 1 month later, 29 were available for repeated radionuclide ventriculography after 12 +/- 5 months. Of these, 15 showed improvement (delta LVEF > or = 5%, mean 10 +/- 5%) and 14 did not (delta LVEF < 5%, mean -1 +/- 3%). The increase in EF with dobutamine had the highest univariate predictive value of all parameters evaluated. The sensitivity, specificity, and positive and negative predictive values of dobutamine radionuclide ventriculography were 67%, 93%, 91%, and 72%, respectively. We conclude that dobutamine radionuclide ventriculography is a useful method to assess contractile reserve and predict ventricular functional improvement after CABG in patients with ischemic cardiomyopathy.
Left ventricular function and exercise capacity were assessed in 79 patients randomised to receive intravenous and oral propranolol (n = 44) or conventional therapy (n = 35) within four hours of onset of their first myocardial infarction. Cineangiocardiography and exercise testing were performed four weeks after infarction to allow for maximum recovery of myocardial function. Left ventriculography showed no improvement in ejection fraction or preservation of regional contractile function in patients treated with propranolol compared with controls. A trend towards smaller end diastolic volumes was seen in the propranolol group (mean (SD) 151(42) ml) compared with controls (167(42) ml). Exercise duration and frequency of angina were not significantly different in the two groups. It is concluded that limitation of infarct size by propranolol does not lead to a significant improvement in ventricular systolic function, although left ventricular dilatation may be reduced. These findings are consistent with the known effect of early intravenous beta blockade which limits infarct size by preservation of subepicardial myocardium.
A group of 73 patients with idiopathic dilated cardiomyopathy were followed up for an average of 22 +/- 7 months to assess the medium term evolution of echocardiographic parameters of left ventricular function and, in particular, the consequences of cardioversion of atrial fibrillation. Seventy nine per cent of patients presented with cardiac failure. Left bundle branch block was observed in 20% and ventricular arrhythmias were frequent in 31%, complex in 62% with episodes of non-sustained ventricular tachycardia in 10% of cases. Left ventricular dilatation was greater in patients with complete left bundle branch block (p less than 0.003). Atrial fibrillation was present in 14 patients (19%) who were generally older than the rest of the study population (p less than 0.02) and was associated with less severe left ventricular dysfunction (p less than 0.01). Return to sinus rhythm was obtained in 9 patients. Echocardiographic data was obtained in 64 patients after an average of 6.2 +/- 1.7 months. Left ventricular function improved during the follow-up period and returned to normal in 12% of cases. Reduction of atrial fibrillation to sinus rhythm was the only predictive factor of normalisation of left ventricular function (p less than 0.02). The changes in left ventricular end diastolic dimension and fractional shortening was less marked in the group of 56 patients in sinus rhythm or chronic atrial fibrillation (normalisation of left ventricular function in 8% of cases) than in the group of 8 patients in which atrial fibrillation was converted to sinus rhythm (normalisation of left ventricular function in 50% of cases).(ABSTRACT TRUNCATED AT 250 WORDS)
Although the effect of systemic vasodilator therapy on left ventricular function in congestive heart failure has been extensively evaluated, little is known about its effect on pulmonary vascular resistance and right ventricular function. Since pulmonary vascular resistance is mediated in part by alpha-adrenergic receptors, we studied the effects of the alpha-adrenergic antagonist prazosin on right ventricular function as determined by a radionuclide ventriculographic technique which assessed right and left ventricular ejection fractions simultaneously. In 11 patients treated for two months with prazosin, right ventricular ejection fraction increased from 0.28 +/- 0.04 to 0.44 +/- 0.07 (p less than 0.01). In 10 patients who received a single dose of prazosin 48 hours after withdrawal of prior prazosin therapy, right ventricular ejection fraction increased from 0.29 to 0.05 to 0.38 +/- 0.06 (p less than 0.02). In nine patients who received a single dose of prazosin during right sided heart catheterization, pulmonary vascular resistance decreased from 358 +/- 70 to 236 +/- 60 dyne-sec-cm -5 (p less than 0.01). These studies suggest that prazosin has beneficial effects on right ventricular function both immediately and long-term in patients with severe congestive heart failure. Although the mechanism of this effect is not known, possibilities include a direct effect of prazosin on the pulmonary vasculature, a secondary reduction in right ventricular afterload due to improved left ventricular performance and a withdrawal of reflex-mediated pulmonary vasoconstriction due to improved left ventricular performance.
Although chronic therapy with amiodarone is an effective means of suppressing ventricular tachycardia, its long-term effects on ventricular function have not been evaluated. Therefore, left ventricular (LV) and right ventricular (RV) ejection fraction (EF) as well as wall motion score were assessed in 21 patients with ventricular tachycardia before therapy and after 2, 6, 10 and 20 weeks of amiodarone therapy. Serum amiodarone levels after 2, 6, 10 and 20 weeks were 1.9 +/- 0.7, 1.7 +/- 0.6, 1.5 +/- 0.6 and 1.5 +/- 0.7 micrograms/ml, respectively. Drug therapy did not significantly affect the mean LVEF (0 weeks 38 +/- 17, 2 weeks 40 +/- 17, 6 weeks 40 +/- 17, 10 weeks 41 +/- 18 and 20 weeks 40 +/- 18%) or the mean RVEF. Neither LV wall motion score nor RV wall motion score were changed significantly during amiodarone therapy. Fourteen patients had a drug-free LVEF less than 40% (mean 28 +/- 7%). Ventricular function in this subgroup was not impaired after 20 weeks of amiodarone therapy (drug-free LVEF 28 +/- 7%, 20 weeks LVEF 29 +/- 9%; drug-free RVEF 42 +/- 13%, 20 weeks RVEF 41 +/- 12%). Ten patients who were evaluated 34 +/- 6 months after initiation of amiodarone therapy had no significant change in LVEF (drug-free 37 +/- 20%, 34 months 43 +/- 20%). Ventricular functional reserve was assessed after 20 weeks of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
Early reperfusion and good antegrade flow are essential in restoring better regional left ventricular function in acute myocardial infarction, but they do not always correlate with the extent of recovery. This study evaluated coronary circulation using the new "pressure wire" technique to measure the direct pressure of the coronary circulation including antegrade and collateral flow before and after reperfusion in patients with acute myocardial infarction, and to clarify the influence of these variables on recovery of left ventricular function in the convalescent stage. Fifty six consecutive patients with first acute myocardial infarction underwent percutaneous transluminal coronary angioplasty(PTCA) for totally occluded or severely narrowed infarct-related lesion and evaluation of coronary circulation using pressure wire. Left ventriculography was analyzed at 1 month after the onset in 41 patients. Treatment variables including reperfusion time, reperfusion modality, Thrombolysis in Myocardial Infarction(TIMI) grade after PTCA, and pressure wire variables were compared with parameters of left ventricular function. Reperfusion time was not related to regional wall motion evaluated by the SD chord of left ventriculography in the infarcted zone. Pressure wire measurements showed a correlation between fractional flow reserve measured after PTCA and infarcted regional wall motion(r = 0.558, p < 0.01). Patients with infarct-related lesion in the right coronary artery showed the magnitude of left ventricular regional wall motion was related to fractional collateral flow reserve(maxQc/Qn) during PTCA(r = 0.768, p < 0.05), but no such relationship was observed in patients with infarct-related lesion in the left anterior descending artery. Fractional flow reserve measured after PTCA varied widely in patients with the same TIMI flow grade, so did not vary with it. The pressure wire technique enables assessment of the collateral circulation distal to infarct-related lesion quantitatively before reperfusion in patients with acute myocardial infarction. The fractional flow reserve derived by coronary pressure after reperfusion was significantly related to the recovery of regional wall motion in the infarcted area in the convalescent stage. The fractional flow reserve after reperfusion with PTCA is a better parameter than TIMI flow grade for predicting recovery of regional left ventricular function after myocardial infarction.