Poor survival of patients with idiopathic cardiomyopathy considered too well for transplantation

Anesthesia for Heart Transplantation

Although several new surgical therapies hold promise for changing the surgical approach to heart failure, the most effective therapy currently for patients with end- stage congestive heart failure is heart transplantation. The challenges posed to the anesthesiologist caring for these patients are great, and are increasing as a result of a shift toward transplanting medically unstable pa tients. The anesthetic management of patients undergo ing heart transplantation requires a knowledge of the pathophysiology of heart failure, the altered pharmacody namics of anesthetics in the patient with heart failure, treatment of right heart failure, as well as the impact of new surgical therapies on cardiovascular function.

Outcome after mitral valve operations with depressed left ventricular function

We retrospectively investigated 42 patients (27 men, 15 women; mean age, 67 years) with severe mitral valve incompetence and endstage cardiomyopathy (ejection fraction<30%) who were operated on between January 2002 and March 2009. Of these, 14 were in New York Heart Association class IV, and 27 were in class III. The etiology was ischemic in 18 patients and idiopathic dilated in 24. Mitral valve repair was performed in 25 patients, and 17 had mitral valve replacement. The mean logistic EuroSCORE was 33.41. The mean follow-up was 44.52 months. There were no perioperative deaths. Three patients died within 30 days postoperatively. Thirty-day mortality was lower than predicted by EuroSCORE (7.14% vs. 33.41%). The median functional class improved from 3 to 2 during follow-up. Ejection fraction improved from 24% to 42% at 6 weeks, then decreased to 33%. The midterm survival rate was 86%, and 81% after 1 and 2 years. Freedom from reoperation at 2 years was 85%; 6 patients needed reoperation for recurrent mitral regurgitation. Despite high operative risk, mitral valve surgery can be performed successfully with acceptably low mortality in patients with endstage cardiomyopathy. Patients experience substantial clinical improvement and a moderate recovery of left ventricular function.

Surgical treatment of functional mitral regurgitation in dilated cardiomyopathy

Functional mitral regurgitation is a significant complication of end-stage cardiomyopathy. Dysfunction of one or more components of the mitral valve apparatus occurs in 39-74% and affects almost all heart failure patients. Survival is decreased in subjects with more than mild mitral regurgitation irrespective of the aetiology of heart failure. The goal of treating functional mitral regurgitation is to slow or reverse ventricular remodelling, improve symptoms and functional class, decrease the frequency of hospitalization for congestive heart failure, slow progression to advanced heart failure (time to transplant) and improve survival. This article reviews the role of mitral valve surgery in patients with heart failure and dilated cardiomyopathy.

Effectiveness of surgical ventricular restoration in patients with dilated ischemic cardiomyopathy and unrepaired mild mitral regurgitation

OBJECTIVE

Any grade of ischemic mitral regurgitation is associated with excess mortality. Whether mild ischemic mitral regurgitation should be repaired at the time of either coronary artery bypass grafting or surgical ventricular restoration is controversial. Surgical ventricular restoration is a treatment option for dilated post-infarction cardiomyopathy and has the potential to improve mitral functioning. The present study assessed the effectiveness of surgical ventricular restoration and unrepaired mild ischemic mitral regurgitation on left ventricular geometry, cardiac and functional status, and survival.

METHODS

We analyzed 55 patients with previous anterior infarction (age 65 +/- 10 years) and mild chronic functional mitral regurgitation who underwent surgical ventricular restoration and coronary artery bypass grafting without mitral repair at our center. Left ventricular volumes, ejection fraction, and geometric parameters were measured before and after surgery.

RESULTS

Even mild ischemic mitral regurgitation is characterized by abnormal left ventricular geometry when compared with that of patients without mitral regurgitation at comparable ventricular volumes and ejection fraction. Surgical ventricular restoration induces a significant decrease in left ventricular volumes, left ventricular diameters, and papillary muscle distance; and an improvement in ejection fraction and New York Heart Association class. Ischemic mitral regurgitation significantly decreases in the majority of patients. Survival is 93% at 1 year and 88% at 3 years.

CONCLUSION

Surgical ventricular restoration improves mitral functioning by improving geometry abnormalities. Survival is optimal and greater than would be expected in patients with post-infarction dilated ventricles and depressed left ventricular function. Our data indicate that mitral repair in conjunction with surgical ventricular restoration is unnecessary in such patients.

Clinical Efficacy of Surgical Heart Failure Therapy by Ventricular Restoration and Restrictive Mitral Annuloplasty

BACKGROUND

Treatment of heart failure by advanced surgical procedures such as ventricular restoration (SVR) and restrictive mitral annuloplasty (RMA) is increasingly applied. We studied clinical efficacy of heart failure surgery in patients with severe heart failure.

METHODS AND RESULTS

Thirty-three patients (New York Heart Association (NYHA) class III/IV, left ventricular ejection fraction < or =35%) were included. Patients with moderate to severe mitral regurgitation underwent RMA (85%) and patients with anteroseptal aneurysm underwent SVR (52%). A combined procedure was performed in 12 patients, and additional coronary artery bypass grafting in 27 patients. Clinical and echocardiographic parameters were assessed at baseline and 6 months after surgery. Operative mortality was 3% (n = 1), in-hospital mortality was 9% (n = 3), and there was no late mortality. All clinical parameters were significantly improved at 6 months' follow-up (P < .001); NYHA class improved from 3.4 +/- 0.5 to 1.5 +/- 0.5, Quality-of-life score improved from 44 +/- 22 to 16 +/- 12, and 6-minute walking distance increased from 248 +/- 134 m to 422 +/- 113 m. Left ventricular end-diastolic volume decreased from 107 +/- 32 to 80 +/- 20 mL/m(2) (P < .001) and end-systolic volume decreased from 78 +/- 32 to 53 +/- 15 mL/m(2) (P < .001), whereas ejection fraction improved from 29 +/- 9 to 35 +/- 7% (P < .01).

CONCLUSIONS

Surgical treatment of severe heart failure by SVR or RMA was associated with 12% mortality at 6 months. Surviving patients showed highly significant functional and clinical improvements.

Prognostic Value of Pacing-Induced Mechanical Alternans in Patients With Mild-to-Moderate Idiopathic Dilated Cardiomyopathy in Sinus Rhythm

OBJECTIVES

The relation between the occurrence of pacing-induced mechanical alternans and prognosis in patients with mild-to-moderate idiopathic dilated cardiomyopathy (IDCM) in sinus rhythm was investigated prospectively. The myocardial expression of genes for Ca2+-handling proteins in such patients was also examined.

BACKGROUND

Mechanical alternans occurs in some patients with severe heart failure, but the relation between the occurrence of mechanical alternans and prognosis in patients with IDCM has remained unknown.

METHODS

Left ventricular (LV) pressure was measured during atrial pacing, and LV endomyocardial biopsy specimens were collected in 36 IDCM patients and 8 controls. Idiopathic dilated cardiomyopathy patients were divided into two groups consisting of 22 individuals who did not develop mechanical alternans at heart rates up to 140 beats/min (group A) and of 14 individuals who did (group B). The patients were followed up for a mean of 3.7 years.

RESULTS

There was no significant difference in LV ejection fraction or the plasma concentration of brain natriuretic peptide between groups A and B. The myocardial abundance of ryanodine receptor 2 messenger ribonucleic acid (mRNA) was significantly lower in groups A and B than in controls, whereas that of sarcoplasmic reticulum Ca2+-ATPase mRNA was significantly lower in group B than in group A or controls. Stepwise multivariate analysis identified pacing-induced mechanical alternans as the strongest predictor of cardiac events. Event-free survival in group A was significantly greater than that in group B.

CONCLUSIONS

The occurrence of pacing-induced mechanical alternans is a potentially useful indicator of poor prognosis in patients with mild-to-moderate IDCM in sinus rhythm.

Echocardiographic predictors of morbidity and mortality in patients with advanced heart failure: the Beta-blocker Evaluation of Survival Trial (BEST)

OBJECTIVES

The aim of this study was to determine echocardiographic predictors of outcome in patients with advanced heart failure (HF) due to severe left ventricular (LV) systolic dysfunction in the Beta-blocker Evaluation of Survival Trial (BEST).

BACKGROUND

Previous studies indicate that echocardiographic measurements of LV size and function, mitral deceleration time, and mitral regurgitation (MR) predict adverse outcomes in HF. However, complete quantitative echocardiograms evaluating all of these parameters have not been reported in a prospective randomized clinical trial in the era of modern HF therapy.

METHODS

Complete echocardiograms were performed in 336 patients at 26 sites and analyzed by a core laboratory. A Cox proportional-hazards regression model was used to determine which echocardiographic variables predicted the primary end point of death or the secondary end point of death, HF hospitalization, or transplant. Significant variables were then entered into a multivariable model adjusted for clinical and demographic covariates.

RESULTS

On multivariable analysis adjusted for clinical covariates, only LV end-diastolic volume index predicted death (events = 75), with a cut point of 120 ml/m(2). Three echocardiographic variables predicted the combined end point of death (events = 75), HF hospitalization (events = 97), and transplant (events = 9): LV end-diastolic volume index, mitral deceleration time, and the vena contracta width of MR. Optimal cut points for these variables were 120 ml/m(2), 150 ms, and 0.4 cm, respectively.

CONCLUSIONS

Echocardiographic predictors of outcome in advanced HF include LV end-diastolic volume index, mitral deceleration time, and vena contracta width. These variables indicate that LV remodeling, increased LV stiffness, and MR are independent predictors of outcome in patients with advanced HF.

Update on Mitral Repair in Dilated Cardiomyopathy

Heart failure is one of the leading causes of hospitalization worldwide. Mitral regurgitation (MR) is a known complication of end-stage cardiomyopathy and is associated with a poor prognosis due to progressive mitral annular dilation. A vicious cycle of continuing volume overload, ventricular dilation, progression of annular dilation, increased LV wall tension, and worsening of MR and CHF occur. Commonly, these patients were managed medically with diuretics and afterload reduction, and frequently with mitral valve replacement, both of which have poor long term survival in patients with CHF and MR. Over a 10-year period we prospectively studied over 200 patients with cardiomyopathy and severe MR who underwent mitral valve repair utilizing an undersizing overcorrecting annuloplasty ring. The mortality was low with one intraoperative death and eight 30-day mortalities. There were 26 late deaths; 2 of these patients had progression of heart failure and underwent transplantation. The 1-, 2-, and 5-year actuarial survivals have been 82%, 71%, and 52%, respectively. The NYHA class has improved for all patients from a preoperative mean of 3.2 +/- 0.2 to 1.8 +/- 0.4 postoperatively. All patients demonstrated improvement in ejection fraction, cardiac output, and end diastolic volumes with a reduction in sphericity index and regurgitant volume at 2 years post operation. All of the observed changes contribute to reverse remodeling and restoration of the normal left ventricular geometry. Mitral valve repair is a safe and effective operative intervention that corrects MR and offers a new strategy for patients with MR and end-stage cardiomyopathy.

Mechanisms underlying ventricular arrhythmias in idiopathic dilated cardiomyopathy: implications for management

Ventricular arrhythmias (VA) have been associated with mortality in idiopathic dilated cardiomyopathy (IDCM). All 3 main mechanisms of arrhythmogenesis - reentry, trigger activity, and automatism - have been implicated. Arrhythmogenic substrates in IDCM favor these mechanisms and are often potentiated by electrolyte imbalance secondary to diuretic treatment, by antiarrhythmic drugs, or by bradycardia, leading to polymorphic ventricular tachycardia (VT). Myocardial macroreentry is the mechanism most frequently responsible for monomorphic VT in IDCM; however, focal activation and His-Purkinje macroreentry are often responsible and, especially in the latter case, are frequently unrecognized. Clinical suspicion and final recognition by electrophysiologic testing have important therapeutic consequences, because both focal activation and His-Purkinje macroreentry can be treated effectively by catheter ablation. On the other hand, the frequent recurrences of myocardial macroreentrant VT after ablation require this therapy to be used in combination with drugs or an implantable cardioverter defibrillator (ICD). beta-Adrenoceptor antagonists (beta-blockers) have a beneficial effect for primary prevention of VA in IDCM. Type III antiarrhythmics have a neutral effect on mortality and type I antiarrhythmics should be avoided. Treatment of nonsustained VT in IDCM is controversial because it often presents without symptoms and is linked more to overall mortality than to arrhythmic mortality. Empiric treatment with amiodarone or electrophysiologically guided sotalol are preferred to the use of other drugs for secondary prevention of sustained VA. ICDs should be implanted in patients who have been resuscitated from cardiac arrest due to VA, or in those with poorly tolerated VT and severe left ventricular dysfunction. Empiric treatment with amiodarone or electrophysiologically guided class III antiarrhythmics may also be alternatives for patients with IDCM and no severe left ventricular dysfunction, especially if VT is well tolerated.

Catheter-Based Approach to Mitral Regurgitation

Mitral Regurgitation (MR) is a common medical problem. MR is also a prognostic factor; patients with severe symptomatic MR have a poor prognosis with an annual mortality rate of 5% without surgical intervention. An anatomic understanding of the normal and regurgitant mitral valve is essential in order to evaluate appropriately the severity and impact of MR. We briefly discuss mitral complex anatomy, MR evaluation, and treatment options (surgical and catheter-based alternatives) according to the type of lesion found. In particular, our group has shown temporal percutaneous annuloplasty and definitive percutaneous edge-to-edge mitral valve repair to be a feasible technique. Recently a study evaluating endovascular mitral valve edge-to-edge repair was successfully initiated by our group. Acute and chronic ischemic mitral regurgitation and special situations, such as paravalvular leaks, hypertrophic obstructive cardiomyopathy, and mixed lesions are also discussed. Future directions may include the percutaneous transcatheter implantation of a bioprosthetic valve in mitral position.

Early and midterm clinical outcome in patients with severe left ventricular dysfunction undergoing coronary artery surgery

BACKGROUND

Patients presenting with severe left ventricular (LV) dysfunction undergoing coronary artery surgery are at increased risk of perioperative morbidity and mortality. The present study investigated early and midterm outcomes in a consecutive series of patients with severe LV dysfunction undergoing coronary surgery at our institution.

METHODS

Data on 5,195 consecutive patients undergoing coronary artery bypass grafting (CABG) alone (in-hospital mortality 1.35%) from April 1996 to August 2002 were prospectively recorded in the Patient Analysis and Tracking System. Two hundred and fifty patients (median age 65 years [interquartile range, 57 to 70]) with preoperative left ventricular ejection fraction less than 30% (74 off pump; 29.6%) were identified and early and midterm clinical outcomes analyzed. Propensity scores were used to take account of the imbalance in the distribution of prognostic factors between the on-pump and off-pump groups.

RESULTS

Patients undergoing on-pump surgery were less likely to have current congestive heart failure, insulin-dependent diabetes, a history of hypertension, have had gastrointestinal tract surgery or an ulcer, or unstable angina. They had on average lower Parsonnet scores and New York Heart Association and Canadian Cardiovascular Score ratings. However they were more likely to have more extensive coronary artery heart disease and to require more grafts than those undergoing off-pump surgery. After adjustment for consultant team and propensity scores no differences between groups with regard to in-hospital mortality and morbidity were found. The only in-hospital outcome to show a significant difference after adjustment was the need for intraoperative inotropic support, which was higher in the on-pump group (odds ratio 5.1; 95% confidence interval 2.55 to 10.2; p < 0.001)). The median follow-up times for the on- and off-pump groups were 3.4 years and 1.4 years respectively. Three-year survival was higher with on-pump surgery (87% on-pump versus 73% off-pump) but this difference did not reach statistical significance after adjustment for prognostic variables (hazard ratio 0.54, 95% confidence interval 0.22 to 1.26, p = 0.16).

CONCLUSIONS

In-hospital mortality and morbidity in patients presenting with severe LV dysfunction is low with comparable results with both on- and off-pump coronary artery surgery. Midterm clinical outcome is encouraging and seems to justify surgical revascularization for this high-risk group of patients.

Prognostic significance of heart rate variability in dilated cardiomyopathy

BACKGROUND

Identifying high-risk individuals among patients with nonischemic dilated cardiomyopathy (DCM) is a major and unsolved task of clinical cardiology. We aimed to determine prognostic significance of heart rate variability (HRV) for predicting cardiac events in DCM patients with markedly depressed left ventricular function.

METHODS

In 69 DCM patients in sinus rhythm, with normal coronary angiography and mean ejection fraction 32 (11%) cardiac events defined as cardiac death or heart transplantation during a mean 20-month follow-up were related to baseline time-domain HRV parameters calculated from 24-h digital Holter monitoring.

RESULTS

There were 18 (26%) cardiac events (10 deaths and 8 heart transplantations). In multivariate Cox analysis, standard deviation of normal-to-normal intervals (SDNN) (hazard ratio: 1.35; 95% confidence interval 1.11-1.63; P=0.002) and ejection fraction (hazard ratio: 4.21; confidence interval 1.64-10.78; P=0.003) were significant and independent predictors of cardiac events. One-year event-free survival was significantly lower in patients with SDNN<80 ms compared to those with SDNN>or=80 ms (35% vs. 89%, respectively; P<0.00005). Low SDNN was identifying high-risk patients among those with both depressed and relatively preserved left ventricular function.

CONCLUSIONS

Broadly available time-domain HRV analysis adds independent prognostic information improving risk stratification of DCM patients and therefore it should be incorporated in routine clinical evaluation to determine patients' priority for heart transplantation.

The prognostic value of body mass index and standard exercise testing in male veterans with congestive heart failure

OBJECTIVE

To evaluate the prognostic characteristics of body mass index (BMI) and standard exercise test variables in a consecutive series of patients with mild to moderate congestive heart failure (CHF) referred for standard exercise tests.

BACKGROUND

Controversy exists regarding the prognostic importance of BMI, etiology, and exercise test variables in patients with CHF.

METHODS

All patients referred for evaluation at two university-affiliated Veterans Affairs Medical Centers who underwent treadmill tests for clinical indications between 1987 and 2000 were determined to be dead or alive using the Social Security Death Index after a mean 6 years follow-up. Clinical and exercise test variables were collected prospectively according to standard definitions; testing and data management were performed in a standardized fashion using a computer-assisted protocol. Survival analysis was performed using all-cause mortality as the endpoint for follow-up.

RESULTS

A total of 522 patients with a history and clinical findings of CHF underwent exercise testing. Forty-two percent died during the follow-up period, for an average annual mortality of 6.7%. Cox proportional hazards model chose peak metabolic equivalents (METs), BMI, age, and ischemic etiology in rank order as independently and significantly associated with time to death. A score based on these variables classified patients into low (2% annual mortality), medium (5.2%), and high-risk groups (7% annual mortality).

CONCLUSION

Standard exercise testing and BMI can be used to estimate prognosis in outpatients with heart failure. A score incorporating METs, BMI, age, and etiology efficiently stratified these patients. BMI was chosen by the survival analysis, confirming its surprising inverse relationship to prognosis in CHF patients (i.e., heavier patients do better).

Prevalence and incidence of arrhythmias and sudden death in heart failure

Patients with heart failure are prone to a variety of arrhythmias, symptomatic and asymptomatic, that are prognostically significant and have an important bearing on the management of these patients. However there are some inherent problems in assessing the frequency of these arrhythmias within a large patient population, due to a lack of uniformity in defining heart failure and the transient nature of these rhythms. Patients with heart failure commonly die suddenly. The causes of these deaths are difficult to ascertain accurately and are often presumed arrhythmic. With the advent of effective interventions to prevent sudden death, accurately defining the causal relationship between the arrhythmias and sudden death has assumed great importance to appropriately target therapy. Several attempts have been made to predict such deaths on the basis of non-invasive and invasive diagnostic investigations with variable success. In this article we review the incidence and prevalence of atrial and ventricular arrhythmias and sudden deaths in epidemiological studies, surveys and randomised control trials of patients with heart failure. We discuss the prognostic significance of these arrhythmias, the inherent problems in their diagnosis and whether their presence predicts the risk of sudden deaths and the mode of such deaths in the heart failure population. The role of various investigations in risk stratification of sudden death has also been discussed.

Prognostic value of mechanical efficiency in ambulatory patients with idiopathic dilated cardiomyopathy in sinus rhythm

OBJECTIVES

The purpose of this study was to determine, by analyzing the pressure-volume relationship, the prognostic value of parameters related to myocardial energetics for predicting mortality in patients with dilated cardiomyopathy (DCM) in sinus rhythm.

BACKGROUND

The relationship between the myocardial energetics and the prognosis of patients with DCM in sinus rhythm remains unclear.

METHODS

We followed 114 ambulatory patients with nonischemic DCM in sinus rhythm for a mean period of 5.8 +/- 3.9 years. Over 70% of our patients were in New York Heart Association functional class I and class II. Pressure-volume data were obtained by the conductance method, and myocardial oxygen consumption per beat (VO(2)) measurements were obtained.

RESULTS

The 3-, 5-, and 10-year cumulative survival rates were 88.6%, 80.0%, and 73.9%, respectively. Of the 114 patients, 47 were selected randomly to assess their myocardial energetics. By univariate analysis, the mechanical efficiency (ME, external work/VO(2)), left ventricular (LV) ejection fraction and the LV end-diastolic pressure were statistically associated with cardiac death. The ME was the strongest predictor of survival in a Cox proportional-hazards analysis (p = 0.011). The best cutoff point of ME identified by the receiver-operating curve was 11%. This value had a sensitivity of 100%, a specificity of 87% and an overall predictive accuracy of 88% to distinguish survivors from nonsurvivors.

CONCLUSIONS

This study clearly demonstrates that ME is a powerful clinical predictor for cardiac death in patients with mild to moderate heart failure and with sinus rhythm. Whether these conclusions apply to patients with more severe heart failure requires further investigations.

Primary prevention of sudden cardiac death in idiopathic dilated cardiomyopathy: the Cardiomyopathy Trial (CAT)

BACKGROUND

Patients with idiopathic dilated cardiomyopathy (DCM) and impaired left ventricular ejection fraction have an increased risk of dying suddenly.

METHODS AND RESULTS

Patients with recent onset of DCM (< or =9 months) and an ejection fraction < or =30% were randomly assigned to the implantation of an implantable cardioverter-defibrillator (ICD) or control. The primary end point of the trial was all-cause mortality at 1 year of follow-up. The trial was terminated after the inclusion of 104 patients because the all-cause mortality rate at 1 year did not reach the expected 30% in the control group. In August 2000, the vital status of all patients was updated by contacting patients, relatives, or local registration offices. One hundred four patients were enrolled in the trial: Fifty were assigned to ICD therapy and 54 to the control group. Mean follow-up was 22.8+/-4.3 months, on the basis of investigators' follow-up. After 1 year, 6 patients were dead (4 in the ICD group and 2 in the control group). No sudden death occurred during the first and second years of follow-up. In August 2000, after a mean follow-up of 5.5+/-2.2 years, 30 deaths had occurred (13 in the ICD group and 17 in the control group). Cumulative survival was not significantly different between the two groups (93% and 80% in the control group versus 92% and 86% in the ICD group after 2 and 4 years, respectively).

CONCLUSIONS

This trial did not provide evidence in favor of prophylactic ICD implantation in patients with DCM of recent onset and impaired left ventricular ejection fraction.

Mitral valve reconstruction in the patient with heart failure

Secondary MR is a complication of end-stage cardiomyopathy and is associated with a poor prognosis and is due to progressive mitral annular dilation and alteration in LV geometry. A vicious cycle of continuing volume overload, ventricular dilation, progression of annular dilation, increased LV wall tension and worsening MR and CHF occur. The mainstay of medical therapy is diuretics and afterload reduction, and is associated with poor long-term survival in these patients with CHF and MR. However, surgical intervention in the form of undersized, 'overcorrecting' mitral valve repair has shown great promise and is an area of ongoing investigation.

Characteristics of patients referred for cardiac transplantation: implications for the donor organ shortage

BACKGROUND

When the decision is made to proceed with cardiac transplantation, the risk/benefit ratio for continued medical therapy in that particular patient must be weighed against the risk/benefit ratio associated with cardiac transplantation. This can only be accomplished while the patient is on maximal medical therapy.

METHODS

To better define the appropriateness of patients being referred for consideration of transplant, we examined the records of 100 consecutive adult patients referred to a cardiac transplant program.

RESULTS

Two of five patients referred for transplantation had at least one contraindication for transplantation. Twenty percent of the patients were not treated with angiotensin-converting enzyme inhibitors and did not have any documented reason for undertreatment. Of those deemed too well for cardiac transplantation, 84% were alive and either class I or II (mean follow-up 21 months).

CONCLUSIONS

We found the majority to be undertreated or with an absolute contraindication to transplantation. Of those deemed too well for transplantation after appropriate treatment, 84% were alive and well.

Mitral valve repair in heart failure

Mitral regurgitation (MR) is a frequent complication of end-stage heart failure. Historically, these patients were either managed medically or with mitral valve replacement, both associated with poor outcomes. Mitral valve repair via an 'undersized' annuloplasty repair is safe and effectively corrects MR in heart-failure patients. All of the observed changes contribute to reverse remodeling and restoration of the normal left-ventricular geometric relationship. Mitral valve repair offers a new strategy for patients with MR and end-stage heart failure.

Surgical alternatives to transplantation and assist devices in the treatment of heart failure

It is estimated that in the United States 30,000 patients with end-stage heart disease are eligible for heart transplantation, although less than 2500 are actually performed each year. As the population ages, several thousand other patients who are ineligible for cardiac transplantation will be left with limited options. Surgical strategies aimed at halting the progression of heart failure have therefore been devised. High-risk coronary artery bypass grafting can improve ejection fraction and alleviate heart failure symptoms in appropriately selected patients. Mitral valve repair and ventricular aneurysm resection/plication procedures may improve heart failure by decreasing the volume load on the left ventricle. Myoreduction operations (Batista operation) aim to improve the volume and wall stress relationship of the dilated left ventricle, but their clinical application has remained experimental.

Design and implementation of the North American Pediatric Cardiomyopathy Registry

The Pediatric Cardiomyopathy Registry (PCMR) was established to describe the epidemiologic features and clinical course of selected cardiomyopathies in patients aged 18 years or younger and to promote the development of etiology-specific treatments. Sixty-one private and institutional pediatric cardiomyopathy practices in the United States and Canada were recruited to participate in the PCMR. The registry consists of a prospective, population-based cohort of patients in 2 regions (New England and the Central Southwestern United States) and a retrospective cohort of patients diagnosed between 1991 and 1996. Annual follow-up data are collected on all patients. As of June 1999, the PCMR consisted of 337 prospectively identified and 990 retrospectively identified patients. The PCMR has demonstrated the feasibility of establishing a large database of sociodemographic and clinical information on children with pediatric cardiomyopathy. Through this cooperative effort, the PCMR will obtain precise estimates of the incidence of pediatric cardiomyopathy and a better understanding of the natural history of this disease.

Cardiopulmonary exercise testing and prognosis in severe heart failure: 14 mL/kg/min revisited

BACKGROUND

Accurately establishing prognosis in severe heart failure has become increasingly important in assessing the efficacy of treatment modalities and in appropriately allocating scarce resources for transplantation. Peak exercise oxygen uptake appears to have an important role in risk stratification of patients with heart failure, but the optimal cutpoint value to separate survivors from nonsurvivors is not clear.

METHODS

Six hundred forty-four patients referred for heart failure evaluation over a 10-year period participated in the study. After pharmacologic stabilization at entrance into the study, all participants underwent cardiopulmonary exercise testing. Survival analysis was performed with death as the end point. Transplantation was considered a censored event. Four-year survival was determined for patients who achieved peak oxygen uptake values greater than and less than 10, 11, 12, 13, 14, 15, 16, and 17 mL/kg/min.

RESULTS

Follow-up information was complete for 98.3% of the cohort. During a mean follow-up period of 4 years, 187 patients (29%) died and 101 underwent transplantation. Actuarial 1- and 5-year survival rates were 90.5% and 73.4%, respectively. Peak ventilatory oxygen uptake (VO(2)) was an independent predictor of survival and was a stronger predictor than work rate achieved and other exercise and clinical variables. A difference in survival of approximately 20% was achieved by dichotomizing patients above versus below each peak VO(2) value ranging between 10 and 17 mL/kg/min. Survival rate was significantly higher among patients achieving a peak VO (2) above than among those achieving a peak VO (2) below each of these values (P <.01), but each cutpoint was similar in its ability to separate survivors from nonsurvivors.

CONCLUSION

Peak VO (2) is an important measurement in predicting survival from heart failure, but whether an optimal cutpoint exists is not clear. Peak VO(2) may be more appropriately used as a continuous variable in multivariate models to predict prognosis in severe chronic heart failure.

The health care costs of heart failure in Sweden

AIM

Heart failure is a common and serious condition requiring extensive health care resources. The aim of this study is to estimate the total treatment costs of heart failure in Sweden.

METHODS AND RESULTS

The study is a prevalence-based cost-of-illness study. It includes costs of institutional care (hospitals and nursing homes), outpatient care, surgery and drugs. The costs are estimated based on official Swedish statistics, and on various clinical and epidemiological studies. The results are expressed in 1996 prices. The total annual treatment costs for heart failure are approximately Swedish kronor (SEK) 2000-2600 million, or nearly 2% of the Swedish health care budget. Institutional care is the single largest component, amounting to SEK 1300-1900 million, or about 65-75% of the costs of heart failure treatment.

CONCLUSIONS

The results from this study indicate that heart failure is a costly condition. Efforts to develop effective management programmes that can reduce the need for expensive institutional care, without a negative impact on quality of life, morbidity and mortality, should be given high priority.

Intermediate-term outcome of mitral reconstruction in cardiomyopathy

OBJECTIVE

Severe mitral regurgitation is a frequent complication of end-stage cardiomyopathy that contributes to heart failure and predicts a poor survival. We studied the intermediate-term outcome of mitral reconstruction in 48 patients who had cardiomyopathy with severe mitral regurgitation and were operated on between June 1993 and June 1997.

METHODS

Ages ranged from 33 to 79 years (63 +/- 6 years) with left ventricular ejection fractions of 8% to 25% (16% +/- 3%). All patients were receiving maximal drug therapy and were in New York Heart Association class III-IV with severe, refractory 4+ mitral regurgitation. Operatively, all 48 had undersized flexible annuloplasty rings inserted, 7 had coronary bypass grafts for incidental disease, 11 had prior bypass grafts, and 11 also had tricuspid valve repair.

RESULTS

One operative death occurred as a result of right ventricular failure. Postoperative transesophageal echocardiography revealed mild mitral regurgitation in 7 patients and no mitral regurgitation in 41. There were 10 late deaths, 2 to 47 months after mitral reconstruction. The 1- and 2-year actuarial survivals have been 82% and 71%. At a mean follow-up of 22 months, the number of hospitalizations for heart failure has decreased, and 1 patient has had heart transplantation. Significantly, New York Heart Association class improved from 3.9 +/- 0.3 before the operation to 2.0 +/- 0.6 after the operation. Twenty-four months after the operation, left ventricular volume and sphericity have decreased, whereas ejection fraction and cardiac output have increased.

CONCLUSION

Whether this favorable modification of left ventricular function and geometry will persist remains unknown. However, mitral repair for cardiomyopathy with mitral regurgitation allows new strategies for these patients.

Assessment of the appropriateness of the decision of heart transplantation in idiopathic-dilated cardiomyopathy

One hundred thirty patients with idiopathic-dilated cardiomyopathy were referred for heart transplantation to our center and followed for 18 months. Heart transplantation was performed on 63 patients, 17 patients died before transplantation due to heart failure, and 50 patients never had transplantation. Clinical, electrocardiographic, echocardiographic, and hemodynamic data of the 50 nontransplanted survivors and the 17 patients who died were used to identify independent risk variables with discriminant analysis. Using a statistical model based on the results of discriminant analysis, each of the remaining 63 transplanted patients were predicted as being alive or dead in absence of transplantation. The discriminant analysis identified right atrial pressure, cardiac index, and the New York Heart Association functional class as the strongest predictors of 18-month outcome. The accuracy of the model in predicting survival without transplantation in the nontransplanted group of patients, based on the concordance between actual and predicted outcome, was 85% (kappa = 0.62). Subsequent application of this model to the transplanted group of patients suggested that the decision for transplantation was appropriate in 41 of the 63 patients, and could have been premature in the remaining 22 patients predicted as alive. These results suggest that two-thirds of patients receiving transplants would have died without intervention, but the decision to transplant could have been premature in the remaining patients.

Recipient selection and management before cardiac transplantation

Cardiac transplantation is a proven, effective therapy for selected patients with end-stage congestive heart failure. Recipient selection is performed by a multidisciplinary team consisting of transplant physicians and surgeons. Clinicians responsible for patient assessment must establish the severity of cardiac dysfunction, formulate a prognosis, and stratify patients according to risk for mortality. Patients whose survival and quality of life are most limited without cardiac transplantation are candidates for therapy. The scarcity of organ donors makes careful screening of potential recipients necessary to identify those individuals most likely to obtain a long-term benefit. Recipient selection criteria and management strategies are evolving because of extended waiting times and high mortality caused by the lack of sufficient numbers of donors. Alternative therapies should be applied wherever possible.

The continuing evolution of mechanical ventricular assistance

A great number of patients suffer and die of the sequelae of acute and chronic heart failure each year. Although advances in medical and surgical therapy have benefited many of these patients, most have disease that is refractory to any definitive therapy. For these patients cardiac transplantation is the only remaining hope. Unfortunately, because of the increasing demand for donor organs in the face of a fixed and limited supply, this option is available to only a small percentage of these patients. Even in patients accepted for transplantation, a significant waiting list mortality has been observed. A variety of VADs have been developed since the first successful case of mechanical cardiac assistance more than 30 years ago. These devices differ in basic mechanical function, method of insertion, and degree of implantability and thus have different indications and potential applications. Whereas the intraaortic balloon pump and centrifugal pumps are effective short-term support modalities, extracorporeal and implantable pulsatile devices have been used successfully for long-term support of patients with reversible and nonreversible cardiac failure. Although these pumps have most commonly been used as bridges to transplantation, increasing clinical experience has supported the notion of long-term mechanical assistance as a definitive therapy for patients with end-stage heart disease. Although complications, particularly infection and thromboembolism, pose significant challenges and long-term device reliability remains to be fully determined, available implantable devices appear to be capable of providing effective long-term support. As data are obtained from currently ongoing trials comparing VAD support with medical therapy for end-stage heart failure, ethical and economic issues will assume increasing importance.

Improvement following correction of secondary mitral regurgitation in end-stage cardiomyopathy with mitral annuloplasty

Twenty consecutive patients with severe mitral regurgitation secondary to end-stage dilated cardiomyopathy underwent mitral annuloplasty for refractory symptoms of heart failure. On follow-up 18 +/- 4 months after annuloplasty, 14 patients (70%) were alive, all 14 noted symptomatic improvement, and quantitative echocardiographic/Doppler demonstrated decreases in left ventricular volume and sphericity accompanied by increases in ejection fraction and forward cardiac output.

Independent and incremental prognostic value of Doppler-derived mitral deceleration time of early filling in both symptomatic and asymptomatic patients with left ventricular dysfunction

OBJECTIVES

This study sought to investigate the relative and incremental prognostic value of demographic, historical, clinical, echocardiographic and mitral Doppler variables in patients with left ventricular systolic dysfunction.

BACKGROUND

The prognostic value of diastolic abnormalities as assessed by mitral Doppler echocardiography has yet to be defined.

METHOD

A total of 508 patients with left ventricular ejection fraction < or = 35% were followed up for a mean (+/- SD) period of 29 +/- 11 months.

RESULTS

During the follow-up period, 148 patients (29.1%) were admitted to the hospital for congestive heart failure, and 100 patients (19.7%) died. By Cox model analysis, Doppler-derived mitral deceleration time of early filling < or = 125 ms (relative risk [RR] 1.93, 95% confidence interval [CI] 1.4 to 3.7), New York Heart Association functional class III or IV (RR 1.49, 95% CI 1.4 to 2.3), ejection fraction < or = 25% (RR 1.85, 95% CI 1.6 to 2.9), third heart sound (RR 2.06, 95% CI 1.8 to 3.2), age > 60 years (RR 1.95, 95% CI 1.8 to 3.1) and left atrial area > 18 cm2 (RR 1.73, 95% CI 1.6 to 2.7) were all found to be independent and additional predictors of all-cause mortality, and deceleration time was the single best predictor (chi-square 37.80). When all these significant variables were analyzed in hierarchic order, after age, functional class, third sound, ejection fraction and left atrial area, deceleration time still added significant prognostic information (global chi-square from 9.2 to 104.7). Also, deceleration time was the strongest independent predictor of hospital admission for congestive heart failure (RR 4.88, 95% CI 3.7 to 6.9) and cumulative events (congestive heart failure or all-cause mortality, or both; RR 2.44, 95% CI 2.0 to 3.8) in both symptomatic and asymptomatic patients.

CONCLUSIONS

Deceleration time of early filling is a powerful independent predictor of poor prognosis in patients with left ventricular systolic dysfunction, whether symptomatic or asymptomatic. A short (< or = 125 ms) deceleration time by mitral Doppler echocardiography adds important prognostic information compared with other clinical, functional and echocardiographic variables.

Transplant candidates with severe left ventricular dysfunction managed with medical treatment: characteristics and survival

OBJECTIVES

This study sought to assess the clinical characteristics and survival of patients with symptomatic heart failure who were referred as potential heart transplant candidates, but were selected for medical management.

BACKGROUND

Patients with severe left ventricular dysfunction referred for heart transplantation may be considered too well to be placed immediately on an active waiting transplant list. The clinical characteristics of this patient group and their survival have not been well defined. These patients represent a unique group that are characterized by comparatively low age and freedom from significant comorbid conditions.

METHODS

We studied 116 consecutive patients with symptomatic heart failure, severe left ventricular dysfunction (left ventricular ejection fraction 20 +/- 7% [mean +/- SD]) and duration of symptoms >1 month referred for heart transplantation, who were acceptable candidates for the procedure but who were not listed for transplantation because of relative clinical stability. These patients were followed up closely on optimal medical therapy. A variety of baseline clinical, hemodynamic and exercise variables were assessed to define this patient group and used to predict cardiac death and requirement later for heart transplantation.

RESULTS

During a mean follow-up period of 25.0 +/- 14.8 months (follow-up 99% complete), there were eight cardiac deaths (7%) (seven sudden, one acute myocardial infarction). Only nine patients (8%) were listed for heart transplantation. Actuarial 1- and 4-year cardiac survival rates were 98 +/- 1% and 84 +/- 7% (mean +/- SE), respectively, and freedom from listing for transplantation was 95 +/- 2% and 84 +/- 7% (mean +/- SE), respectively. Patients were mainly in New York Heart Association functional class II or III and had a preserved cardiac index (2.4 liters/min.m2), pulmonary capillary wedge pressure of 16 +/- 9 mm Hg (mean +/- SD) and maximal oxygen consumption of 17.4 +/- 4.3 ml/min per kg (mean +/- SD). By logistic regression analysis, there was no predictor for cardiac death. Longer duration of heart failure (p = 0.013) and mean pulmonary artery (p < 0.05) and pulmonary systolic (p = 0.014) and diastolic (p < 0.05) pressures correlated significantly with listing for heart transplantation by univariate logistic regression. By multivariate logistic regression, only pulmonary artery systolic pressure (p < 0.004) and duration of heart failure (p < 0.015) remained as predictors for need for later transplantation.

CONCLUSIONS

In the current treatment era, prognosis is favorable in a definable group of transplant candidates despite severe left ventricular dysfunction. This patient group can be identified after intensive medical therapy by stable symptoms, a relatively high maximal oxygen uptake at peak exercise and a preserved cardiac output.

Changes in left ventricular filling during follow-up study in survivors and nonsurvivors of idiopathic dilated cardiomyopathy

The assessment of left ventricular diastolic function by Doppler echocardiography shows both a nonrestrictive and restrictive type of filling in idiopathic dilated cardiomyopathy. These different filling patterns are related to the symptoms of cardiac failure and the prognosis. It remains to be established whether changes of Doppler parameters during follow-up procedures were of clinical relevance. Doppler echocardiography of left ventricular filling was done in 45 patients with idiopathic dilated cardiomyopathy at the time of their diagnosis and repeatedly during a follow-up study of 38 +/- 19 months. The deceleration time of early filling, the maximum early and atrial Doppler velocities and their ratios, as well as echocardiographic parameters of cardiac dimensions and systolic function, were measured. During the follow-up period, seven patients died and four patients underwent heart transplantation because of progressive heart failure. The deceleration time was shorter in patients who died or had to undergo heart transplantation as compared with survivors (119 +/- 43 ms vs 188 +/- 63 ms; P < .005). There was no difference in changes of clinical symptoms in survivors and nonsurvivors. The systolic function improved only in survivors. The difference in deceleration time remained significant between both groups, and it also remained a prognostic discriminator. Peak early velocity increased in nonsurvivors (from 0.66 +/- 0.20 m/s to 0.95 +/- 0.21 m/s; P < .01), while it remained constant in survivors (0.65 +/- 0.17 m/s and 0.67 +/- 0.25 m/s). The peak early/atrial velocity ratio varied widely in either group during the follow-up study, its changes were closely related to the concomitant changes of clinical symptoms (r = .59; P < .005) with a decrease of the peak early/atrial velocity ratio in patients with clinical improvement and an increase of the peak early/atrial velocity ratio in those without clinical improvement. The Doppler echocardiographic deceleration time discriminated between survivors and nonsurvivors in idiopathic dilated cardiomyopathy at the time of the initial diagnostic procedure, and this difference was persistent during the follow-up study. The serial evaluation of patients with idiopathic dilated cardiomyopathy showed a close association of changes in diastolic filling with changes in clinical symptoms.

Initial experience with an implantable hemodynamic monitor

BACKGROUND

Measurement of intracardiac hemodynamic parameters has been limited to brief periods in the acute care setting. We developed and evaluated an implantable hemodynamic monitor that is capable of measuring chronic right ventricular oxygen saturation and pulmonary artery pressure.

METHODS AND RESULTS

The device consists of an electronic controller placed subcutaneously and two transvenous leads placed in the right ventricle (reflectance oximeter) and pulmonary artery (variable capacitance pressure sensor). Implantation was performed in 10 patients with severe left ventricular dysfunction. Average implant pulmonary artery pressures were systolic, 52 +/- 16 mm Hg; diastolic, 29 +/- 11 mm Hg; and mean, 40 +/- 12 mm Hg. The mean right ventricular oxygen saturation at implant was 51%. Provocative maneuvers, including postural changes, sublingual nitroglycerin, and bicycle exercise, demonstrated expected changes in measured oxygen saturation and pulmonary artery pressures over time. At follow-up of 0.5 to 15.5 months, there were no significant differences between pulmonary artery pressures or oxygen saturation values transmitted from the device and simultaneous measurement with balloon flotation catheters. Four of the pulmonary artery leads dislodged and three demonstrated sensor drift, whereas two of the oxygen saturation sensors failed. Four patients died and four received transplants. Pathological study did not demonstrate injury to the right ventricular outflow tract or pulmonic valve.

CONCLUSIONS

Chronic measurement of hemodynamic parameters in the outpatient setting with implantable sensor technology appears to be feasible. The devices are well tolerated without significant untoward effects, and the sensors generally function well over time, providing reliable information. Clinical usefulness remains to be established.

Selection and treatment of candidates for heart transplantation. A statement for health professionals from the Committee on Heart Failure and Cardiac Transplantation of the Council on Clinical Cardiology, American Heart Association

Improved outcome of heart failure in response to medical therapy, coupled with a critical shortage of donor organs, makes it imperative to restrict heart transplantation to patients who are most disabled by heart failure and who are likely to derive the maximum benefit from transplantation. Hemodynamic and functional indexes of prognosis are helpful in identifying these patients. Stratification of ambulatory heart failure patients by objective criteria, such as peak exercise oxygen consumption, has improved ability to select appropriate adult patients for heart transplantation. Such patients will have a poor prognosis despite optimal medical therapy. When determining the impact of individual comorbid conditions on a patient's candidacy for heart transplantation, the detrimental effects of each condition on posttransplantation outcome should be weighed. Evaluation of patients with severe heart failure should be done by a multidisciplinary team that is expert in management of heart failure, performance of cardiac surgery in patients with low left ventricular ejection fraction, and transplantation. Potential heart transplant candidates should be reevaluated on a regular basis to assess continued need for transplantation. Long-term management of heart failure should include continuity of care by an experienced physician, optimal dosing in conventional therapy, and periodic reevaluation of left ventricular function and exercise capacity. The outcome of high-risk conventional cardiovascular surgery should be weighed against that of transplantation in patients with ischemic and valvular heart disease. Establishment of regional specialized heart failure centers may improve access to optimal medical therapy and new promising medical and surgical treatments for these patients as well as stimulate investigative efforts to accelerate progress in this critical area.

Results of revascularization in patients with severe left ventricular dysfunction

BACKGROUND

In patients with coronary artery disease and poor ventricular function (ejection fraction, < 20%), bypass grafting remains a surgical challenge. This study evaluates experience with isolated revascularization in such patients.

METHODS AND RESULTS

In 79 consecutive patients (69 men, 10 women; average age, 59 +/- 9 years), preoperative ejection fraction was 18 +/- 5%. Indications for surgery were congestive heart failure (CHF) in 5 of 79 patients (6%), CHF and angina in 19 (24%), angina in 41 (52%), ventricular arrhythmias (VAs) in 8 (10%), and critical anatomy in 6 (8%). Some patients had prior VAs (23 of 79; 29%) or mitral regurgitation (18; 23%) and required emergent surgery (25; 32%). At surgery, temperature mapping ensured adequate distribution of antegrade cold cardioplegia, with 3.6 +/- 0.7 grafts per patient, including left internal mammary artery graft in 60 of 79 (76%) and endarterectomy in 14 (18%). Hospital mortality was 3.8%. Perioperative support included intra-aortic balloon pump in 18 of 79 (23%) and drugs for VAs in 28 (35%). Morbidity included myocardial infarction in 2 of 79 (2.5%) and stroke in 2 (2.5%). During follow-up, there were 19 late deaths. Actuarial survival was 94%, 82%, and 68% at 1, 2, and 5 years, respectively, and was similar in patients with severe angina, CHF, mitral regurgitation, or VAs. Freedom from sudden death was 100%, 98%, and 91% at 1, 2, and 5 years, respectively. Among survivors, angina improved in 84% and heart failure improved in 26%.

CONCLUSIONS

These data support bypass graft surgery in patients with severe LV dysfunction. With careful cardioplegic techniques, hospital mortality was low (3.8%). Long-term survival is encouraging, with good relief of symptoms in most patients. Perioperative VAs are frequent but respond to medical treatment, with only 23% of patients discharged on antiarrhythmic drugs. Five-year freedom from sudden death is 91%, with only 3 late sudden deaths in this series.

Early outcome of mitral valve reconstruction in patients with end-stage cardiomyopathy

Uncontrollable severe mitral regurgitation is a frequent complication of end-stage cardiomyopathy, significantly contributing to heart failure in these patients, and predicts a poor survival. Although elimination of mitral valve regurgitation could be most beneficial in this group, corrective mitral valve surgery has not been routinely undertaken in these very ill patients because of the presumed prohibitive operative mortality. We studied the early outcome of mitral valve reconstruction in 16 consecutive patients with cardiomyopathy and severe, refractory mitral regurgitation operated on between June 1993 and April 1994. There were 11 men and five women, aged 44 to 78 years (64 +/- 8 years) with left ventricular ejection fractions of 9% to 25% (16% +/- 5%). Preoperatively all patients were in New York Heart Association class IV, had severe mitral regurgitation (graded 0 to 4+ according to color flow Doppler transesophageal echocardiography) and two were listed for transplantation. Operatively, a flexible annuloplasty ring was implanted in all patients. Four patients also had single coronary bypass grafting for incidental coronary disease. In four patients the operation was performed through a right thoracotomy because of prior coronary bypass grafting, and four patients also underwent tricuspid valve reconstruction for severe tricuspid regurgitation. No patient required support with an intraaortic balloon pump. There were no operative or hospital deaths and mean hospital stay was 10 days. There were three late deaths at 2, 6, and 7 months after mitral valve reconstruction, and the 1-year actuarial survival has been 75%. At a mean follow-up of 8 months, all remaining patients are in New York Heart Association class I or II, with a mean postoperative ejection fraction of 25% +/- 10%. There have been no hospitalizations for congestive heart failure, and a decrease in medications required has been noted. For patients with cardiomyopathy and severe mitral regurgitation, mitral valve reconstruction as opposed to replacement can be accomplished with low operative and early mortality. Although longer term follow-up is mandatory, mitral valve reconstruction may allow new strategies for patients with end-stage cardiomyopathy and severe mitral regurgitation, yielding improvement in symptomatic status and survival.

Histomorphometric features predict 1-year outcome of patients with idiopathic dilated cardiomyopathy considered to be at low priority for cardiac transplantation

Cardiac transplantation for patients with idiopathic dilated cardiomyopathy (IDC) and poor left ventricular function usually is postponed until symptoms have become intolerable. However, the short-term prognosis of this subset of patients has been defined poorly. Accordingly, the 1-year outcome was investigated in 30 patients with IDC with an ejection fraction < or = 25% who showed a stabilized clinical condition at assessment for transplantation and were therefore considered at low priority for surgery. During follow-up, 10 patients (group A) showed a poor outcome: 2 died suddenly, and 8 had hemodynamic failure (4 of whom underwent transplantation and 4 of whom died from heart failure while on the waiting list). The remaining 20 patients (group B) had a benign outcome. At assessment for cardiac transplantation, clinical and electrocardiographic features, left ventricular dimension, and ejection fraction were similar between the two groups. However, group A patients had higher left ventricular end-diastolic pressure (p < 0.03) and lower cardiac index (p < 0.02) and stroke volume index (p < 0.03) with respect to group B patients. In addition, the former had a lower myofibril volume fraction (p < 0.001) and a higher nuclear area (p < 0.001) compared with the latter. Multivariate analysis selected myofibril volume fraction (p < 0.001) and nuclear area (p < 0.005) as the only independent predictors of a poor 1-year outcome. The combination of myofibril volume fraction < or = 89% and nuclear area > 50 microns 2 was found in all group A patients (sensitivity 100%) but in only 2 group B patients (specificity 90%). It is concluded that in patients with IDC considered at low priority for cardiac transplantation: (1) the 1-year freedom from a cardiac event is lower than that currently expected with surgery; (2) histomorphometric features, that is, the concurrency of low myofibril volume fraction and increased nuclear area, predict short-term outcome; and (3) endomyocardial biopsy at assessment for cardiac transplantation might improve the rationalization of the timing of the procedure.

Prognostic value of Doppler echocardiographic assessment of left ventricular filling in idiopathic dilated cardiomyopathy

The relation of left ventricular (LV) diastolic filling with the clinical outcome in patients with idiopathic dilated cardiomyopathy (IDC) was examined. LV diastolic filling was assessed by Doppler echocardiography in 57 patients with IDC at the time that the diagnosis was established by angiocardiography. Patients were followed for 29 +/- 16 months. Fifteen patients died: 12 due to progressive congestive heart failure and 3 suddenly. Four other patients underwent cardiac transplantation because of progressive heart failure (1-year survival 86%). Patients who died of congestive heart failure or underwent cardiac transplantation had a steep increase and decrease in the early filling phase as compared with survivors; the peak early Doppler velocity was higher (0.84 +/- 0.16 vs 0.65 +/- 0.21 m/s; p < 0.005), and the deceleration time of the early velocity peak was shorter (117 +/- 26 vs 188 +/- 62 ms; p < 0.001) than in survivors. Surviving patients and those who died suddenly showed similar patterns of LV filling. Deceleration time and peak early Doppler velocity were the strongest predictors of survival as compared with systolic function and clinical status in a Cox proportional-hazards analysis. Patients with a shortened deceleration time (< or = 140 ms) had a significantly reduced 2-year survival rate of 52% (confidence interval 34 to 71%) as compared with those with a longer deceleration time (94%; confidence interval 89 to 98%) (p < 0.001). Evidence was presented for a relation between LV filling and survival in patients with IDC.

Assessing risk by hemodynamic profile in patients awaiting cardiac transplantation

A profile of hemodynamic abnormalities in patients listed for cardiac transplantation was related to survival during the first year after listing. After a patient is listed for cardiac transplantation, the waiting period for a suitable donor heart is often long; therefore, objective criteria to determine risk would be helpful in identifying the group at highest risk of dying before receiving a transplant. Several studies have suggested certain hemodynamic parameters to be related to a poor prognosis. However, no 1 variable has emerged as an adequate predictor of survival in patients awaiting cardiac transplantation. One-year outcomes were examined in 138 consecutive patients listed for cardiac transplantation, who were grouped according to a hemodynamic risk score (HRS) based on abnormalities in baseline measures of right atrial pressure, pulmonary artery systolic pressure, transpulmonary gradient, cardiac output, cardiac index and pulmonary vascular resistance. Right atrial pressure alone was the most significant predictor of survival (p < 0.05). Patients with a right atrial pressure > 12 mm Hg had a 47% 1-year survival as compared with the 68% survival for those with a right atrial pressure < 12 mm Hg. HRS was the next strongest predictor of survival. The 66% survival in group I (HRS = 0) and the 69% survival in group II (HRS = 1 to 3) were significantly (p < 0.03) higher than the 41% survival in group III (HRS = 4 to 6) at 1 year after listing. Differences in survival for the HRS groups could not be explained by left ventricular ejection fraction, left ventricular end-diastolic diameter or status at listing.(ABSTRACT TRUNCATED AT 250 WORDS)

Future developments in implantable cardioverter defibrillators: the optimal device

Despite recent therapeutic advances, SCD remains the leading cause of mortality in industralized nations. The most frequent cause of SCD is ventricular tachyarrhythmias in the setting of advanced structural heart disease due to chronic coronary heart disease or idiopathic dilated cardiomyopathy. Although high-risk groups can be prospectively identified, attempts at primary prevention have been largely unsuccessful. Effective treatment strategies for SCD survivors include antiarrhythmic drug therapy guided by programmed stimulation, endocardial resection, and ICDs. Device therapy has proven extremely effective in preventing recurrent sudden death from ventricular tachyarrhythmias. Widespread application of ICD therapy, perhaps even to include members of high-risk populations that have not experienced cardiac arrest, will depend on many factors including the demonstration that device therapy improves total mortality, not just arrhythmia-related mortality, reduction in cost, and improvements in the devices themselves. Some of the important characteristics of the optimal ICD of the future are nonthoracotomy lead placement; subpectoral generator placement; multiprogrammable, tiered therapy; improved diagnostic specificity, whether based on electrogram or hemodynamic-sensing algorithms; improved integration of brady- and tachy-sensing systems; and enhanced electrogram storage capability with trans-telephonic retrieval of electrogram recordings. The creation of this ideal ICD will obviously require continued technological advances; however, given the tremendous improvements realized over the first three generations of ICD systems, optimism for the future seems warranted.

Clinical and hemodynamic predictors of survival in patients aged < 65 years with severe congestive heart failure secondary to ischemic or nonischemic dilated cardiomyopathy

To identify which clinical or hemodynamic parameters predict survival in patients with end-stage heart failure due to dilated cardiomyopathy, 130 consecutive patients aged < 65 years (mean 46 +/- 13) assessed for heart transplantation from May 1986 to April 1991 were studied. Mean follow-up was 15 +/- 11 months. Left ventricular ejection fraction was 22 +/- 7%. Left ventricular end-diastolic pressure was 27 +/- 9 mm Hg, and cardiac index was 2.2 +/- 0.6 liter/min/m2. Symptom class was IV in 91% of patients and III in 9%. Etiology was ischemic in 40% of patients and idiopathic in 60%. After intensive medical therapy, heart transplantation was considered indicated in 53% of patients, contraindicated in 20% and not indicated in 27%. Transplantation was performed in 36% of patients during follow-up, and 35% died and 29% were alive without transplantation. A comparison, excluding patients with transplantation, was performed between those who were alive and had survived > or = 6 months after assessment, and those who died. On multivariate analysis, the following 3 parameters were independent predictors of prognosis: intravenous inotropic requirement (p < 0.001), maximal, tolerated captopril dose (p = 0.013) and systolic blood pressure (p = 0.003). When patients with transplantation were considered as deaths, stabilization on medical therapy also reached statistical significance (p = 0.009). Classic prognostic markers including ventricular arrhythmias, left ventricular end-diastolic pressure, cardiac index, amiodarone therapy and etiology were not associated with prognosis in this homogeneous population of severely ill patients.