Long-term effects of carvedilol in idiopathic dilated cardiomyopathy with persistent left ventricular dysfunction despite chronic metoprolol. The Heart-Muscle Disease Study Group.

OBJECTIVES: The purpose of this study was to analyze whether long-term treatment with the nonselective beta-adrenergic blocking agent carvedilol may have beneficial effects in patients with dilated cardiomyopathy (DCM), who are poor responders in terms of left ventricular (LV) function and exercise tolerance to chronic treatment with the selective beta-blocker metoprolol. BACKGROUND: Although metoprolol has been proven to be beneficial in the majority of patients with heart failure, a subset of the remaining patients shows long-term survival without satisfactory clinical improvement. METHODS: Thirty consecutive DCM patients with persistent LV dysfunction (ejection fraction < or =40%) and reduced exercise tolerance (peak oxygen consumption <25 ml/kg/min) despite chronic (>1 year) tailored treatment with metoprolol and angiotensin-converting enzyme inhibitors were enrolled in a 12-month, open-label, parallel trial and were randomized either to continue on metoprolol (n = 16, mean dosage 142+/-44 mg/day) or to cross over to maximum tolerated dosage of carvedilol (n = 14, mean dosage 74+/-23 mg/day). RESULTS: At 12 months, patients on carvedilol, compared with those continuing on metoprolol, showed a decrease in LV dimensions (end-diastolic volume -8+/-7 vs. +7+/-6 ml/m2, p = 0.053; end-systolic volume -7+/-5 vs. +6+/-4 ml/m2, p = 0.047), an improvement in LV ejection fraction (+7+/-3% vs. -1+/-2%, p = 0.045), a reduction in ventricular ectopic beats (-12+/-9 vs. +62+/-50 n/h, p = 0.05) and couplets (-0.5+/-0.4 vs. +1.5+/-0.6 n/h, p = 0.048), no significant benefit on symptoms and quality of life and a negative effect on peak oxygen consumption (-0.6+/-0.6 vs. +1.3+/-0.5 ml/kg/min, p = 0.03). CONCLUSIONS: In DCM patients who were poor responders to chronic metoprolol, carvedilol treatment was associated with favorable effects on LV systolic function and remodeling as well as on ventricular arrhythmias, whereas it had a negative effect on peak oxygen consumption.

Long-term survival effect of metoprolol in dilated cardiomyopathy. The SPIC (Italian Multicentre Cardiomyopathy Study) Group.

OBJECTIVE: To evaluate the additive effect of metoprolol treatment on long-term incidence of fatal and non-fatal cardiac events in idiopathic dilated cardiomyopathy. DESIGN: 586 patients with idiopathic dilated cardiomyopathy were prospectively enrolled in a multicentre registry and followed up for a mean (SD) of 52 (32) months. Metoprolol, carefully titrated to the maximum tolerated dose, was added to conventional heart failure treatment in 175 patients. RESULTS: Survival and transplant-free survival at seven years were significantly higher in the 175 metoprolol treated patients than in the remaining 411 on standard treatment (81% v 60%, p < 0.001, and 69% v 49%, p < 0.001, respectively). By multivariate analysis, metoprolol independently predicted survival and transplant-free survival (relative risk reduction values for all cause mortality and combined mortality or transplantation 51% (95% confidence interval 21% to 69%), p = 0.002, and 34% (5% to 53%), p = 0.01, respectively). New York Heart Association class, left ventricular end diastolic diameter, and pulmonary wedge pressure were also predictive. Seven year survival (80% v 62%, p = 0.004) and transplant-free survival (68% v 51%, p = 0.005) were significantly higher in 127 metoprolol treated cases than in 127 controls selected from the entire control cohort and appropriately matched. Metoprolol was associated with a 30% reduction in all cause mortality (7% to 48%, p = 0.015) and a 26% reduction in mortality or transplantation (7% to 41%, p = 0.009). CONCLUSIONS: The addition of metoprolol to standard heart failure treatment, including angiotensin converting enzyme inhibitors, was effective in the long-term, reducing both all cause mortality and transplantation in patients with idiopathic dilated cardiomyopathy.

Spectrum of clinicopathologic manifestations of arrhythmogenic right ventricular cardiomyopathy/dysplasia: a multicenter study.

OBJECTIVES: The aim of the present investigation was to redefine the clinicopathologic profile of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC), with special reference to disease progression and left ventricular (LV) involvement. BACKGROUND: Long-term follow-up data from clinical studies indicate that ARVC is a progressive heart muscle disease that with time may lead to more diffuse right ventricular (RV) involvement and LV abnormalities and culminate in heart failure. METHODS: Forty-two patients (27 male, 15 female; 9 to 65 years old, mean [+/-SD] age 29.6 +/- 18) from six collaborative medical centers, with a pathologic diagnosis of ARVC at autopsy or heart transplantation, and with the whole heart available, were studied according to a specific clinicomorphologic protocol. RESULTS: Thirty-four patients died suddenly (16 during effort); 4 underwent heart transplantation; 2 died as a result of advanced heart failure; and 2 died of other causes. Sudden death was the first sign of disease in 12 patients; the other 30 had palpitations, with syncope in 11, heart failure in 8 and stroke in 3. Twenty-seven patients experienced ventricular arrhythmias (ventricular tachycardia in 17), and 5 received a pacemaker. Ten patients had isolated RV involvement (group A); the remaining 32 (76%) also had fibrofatty LV involvement that was observed histologically only in 15 (group B) and histologically and macroscopically in 17 (group C). Patients in group C were significantly older than those in groups A and B (39 +/- 15 years vs. 20 +/- 8.8 and 25 +/- 9.7 years, respectively), had significantly longer clinical follow-up (9.3 +/- 7.3 years vs. 1.2 +/- 2.1 and 3.4 +/- 2.2 years, respectively) and developed heart failure significantly more often (47% vs. 0 and 0, respectively). Patients in groups B and C had warning symptoms (80% and 87%, respectively, vs. 30%) and clinical ventricular arrhythmias (73% and 82%, respectively, vs. 20%) significantly more often than patients in group A. Hearts from patients in group C weighed significantly more than those from patients in groups A and B (500 +/- 150 g vs. 328 +/- 40 and 380 +/- 95 g, respectively), whereas hearts from both group B and C patients had severe RV thinning (87% and 71%, respectively, vs. 20%) and inflammatory infiltrates (73% and 88%, respectively, vs. 30%) significantly more often than those from group A patients. CONCLUSIONS: LV involvement was found in 76% of hearts with ARVC, was age dependent and was associated with clinical arrhythmic events, more severe cardiomegaly, inflammatory infiltrates and heart failure. ARVC can no longer be regarded as an isolated disease of the right ventricle.

[Clinical polymorphic presentation and natural history of active myocarditis: experience in 60 cases]. / Polimorfismo clinico di presentazione e storia naturale della miocardite attiva: esperienza su 60 casi.

Eight-hundred thirty patients (pts) with suspected myocardial disease of undefined etiology were observed from 1978 to 1996. In 350 pts, the clinical diagnosis was of dilated cardiomyopathy (DCM) or myocarditis. An endomyocardial biopsy was performed on all patients and in 54 of them (15%), an active myocarditis was identified. In six cases, myocarditis was detected at autopsy. There were 37 male patients and 23 females, with an average age of 35.5 +/- 15 years (range 1.67). Mean time interval between clinical onset and diagnosis was 4 +/- 10 months. Clinical presentation was characterized in 4 cases by fulminant myocarditis (Group I), in 8 cases by chest pain (Group II), in 14 cases by arrhythmia (Group III: hypokinetic in 9 pts and hyperkinetic in 5) and, in the last 34 pts, by congestive heart failure (CHF) (Group IV). Improvement was defined at 9 +/- 3 months according to a clinical score based on left ventricular shortening fraction (increase > or = 5 units), New York Heart Association Class improvement by (at least one Class) and left ventricular end-diastolic diameter (decrease > or = 10%). The main clinical and instrumental parameters characterizing the groups were: a more severe dilatation and left ventricular dysfunction in the pts belonging to Group I or IV with respect to those in Group II and III; a significantly worse prognosis in terms of evolution in DCM or death/cardiac transplantation (CT) in the pts from the Group II and III. After a follow-up period of 48 +/- 46 months, the mortality in the four groups was: 100% (4/4), 0% (0/8), 21% (3/14), 38% (13/34). Fifty percent of deaths were concentrated in the first 2 years of follow-up. Left ventricular end-diastolic diameter (OR 1.09, p < 0.05), age (OR 0.95), presence of left ventricular bundle branch block (OR 2.32), right ventricular function (OR 2.43) at clinical onset and the status of improvement at 9 +/- 3 months of follow-up (OR 0.24, p < 0.05) are predictors of evolution in DCM or death/CT for the pts with onset from CHF (Group IV). Immunosuppressive treatment has been utilized for the 76% of the pts. No conclusion can be drawn on the efficacy of this therapy, but no adverse events significantly related to therapy have been observed in a 9 +/- 3 months follow-up period. In conclusion, myocarditis can show a clinical presentation polymorphism, which influences the prognosis and natural history of the disease. Evolution in DCM and adverse events (death/CT) are more common in Groups I and IV. Some simple parameters evaluated at clinical presentation and the proposed classification as "improved" or "not improved" after a short-term follow-up (9 +/- 3 months) show good predictive accuracy. The present study does not allow us to draw any conclusion about the efficacy of immunosuppressive treatment. A randomized, controlled, large-scale trial, with adequate follow-up and advanced histological diagnosis techniques will help define the role of immunosuppressive therapy and patient eligibility criteria for this treatment.

Persistence of restrictive left ventricular filling pattern in dilated cardiomyopathy: an ominous prognostic sign.

OBJECTIVES: We sought to assess the prognostic implications of the evolution of restrictive left ventricular filling pattern (RFP) in dilated cardiomyopathy (DCM). BACKGROUND: Previous work has demonstrated that a RFP in DCM is associated with a poor prognosis. Few data are available on the prognostic implications of the evolution of this pattern. METHODS: The evolution of left ventricular filling was studied by Doppler echocardiography in 110 patients with DCM. According to the left ventricular filling pattern at presentation and after 3 months of treatment, the patients were classified into three groups: Group 1A (n = 24) had persistent restrictive filling; Group 1B (n = 29) had reversible restrictive filling; and Group 2 (n = 57) had nonrestrictive filling. RESULTS: During follow-up (41 +/- 20 months), mortality plus heart transplantations was significantly higher in Group 1A than in Groups 1B and 2 (p < 0.0001). On multivariate analysis, the model incorporating E wave deceleration time at 3 months was more powerful at predicting mortality with respect to this variable at baseline (p = 0.0039). Clinical improvement at 1 and 2 years was significantly more frequent in Groups 1B and 2 than in Group 1A (p < 0.0001 at 2 years). CONCLUSIONS: In patients with DCM, the persistence of restrictive filling at 3 months is associated with a high mortality and transplantation rate. The patients with reversible restrictive filling have a high probability of improvement and excellent survival. Doppler echocardiographic reevaluation of these patients after 3 months of therapy gives additional prognostic information with respect to the initial study.

Epidemiology of dilated cardiomyopathy. A prospective post-mortem study of 5252 necropsies. The Heart Muscle Disease Study Group.

UNLABELLED: Dilated cardiomyopathy is a heart muscle disease of unknown aetiology, characterized by left ventricular dilatation and impaired systolic function. Data on the incidence and prevalence of the disease is ambiguous, due to geographic variations, patient selection and the diagnostic criteria adopted. METHODS: All the post-mortem and clinical cases observed in a consecutive series of 5252 patients resident in Trieste during the period November 1987-November 1989 were studied. RESULTS: Incidence of the disease discovered at autopsy was estimated at 4.5/100,000/year (24 cases), while clinical incidence in the same period was 2.45/100,000/year (13 cases). This is a total incidence of 6.95/100,000 new cases a year. A possible family history of heart muscle disease was found in three patients (12.5%). In 15 patients (62.5%) deaths were due to cardiological complications. Endocardial thickening (P = 0.03), fatty infiltration (P = 0.01) and arterial involvement (P = 0.04) were found more frequently in older patients (> 65 years). CONCLUSIONS: The study confirms that dilated cardiomyopathy in Europe has a higher incidence than previously suggested and emphasizes the need for greater diagnostic sensitivity, particularly since pharmacological treatment is now so effective.

Dystrophin gene abnormalities in two patients with idiopathic dilated cardiomyopathy.

Two new cases of dilated cardiomyopathy (DC) caused by dystrophinopathy are reported. One patient, a 24 year old man, had a family history of X linked DC, while the other, a 52 year old man, had sporadic disease. Each had abnormal dystrophin immunostaining in muscle or cardiac biopsy specimens, but neither had muscle weakness. Serum creatine kinase activity was raised only in the patient with familial disease. Analysis of dystrophin gene mutations showed a deletion of exons 48-49 in the patient with familial DC and of exons 49-51 in the other. Dystrophin transcription in cardiac tissue from the patient with sporadic disease showed abundant expression, predominantly of the muscle isoform. This study, together with previous reports, suggests that some patients with DC have a dystrophinopathy that can be diagnosed using a combination of biochemical and genetic analyses.

Predictive value of heart rate in dilated cardiomyopathy treated with metoprolol.

UNLABELLED: Predictive factors of a favourable response to beta-blocker therapy are still unknown and the role of heart rate remains controversial. AIM: To investigate the relation between heart rate and the response to chronic metoprolol treatment in patients with dilated cardiomyopathy (DCM). METHODS: Ninety-eight consecutive patients with DCM, left ventricular ejection fraction (LVEF) < or = 0.40 and blood pressure < or = 140/90 mmHg were treated with metoprolol, associated with digitalis, diuretics and ACE-inhibitors. After 24 +/- 6 months, 48 patients (49%) were classified as "improved" on the basis of a clinical/instrumental score. RESULTS: Rest, mean 24-hour and maximal exercise heart rate were all significantly and directly related to the probability of improvement, but heart rate at rest, supine and in upright position, showed the highest predictive power. The relationship between heart rate and improvement with metoprolol appeared to be non-linear, with an increasing probability in patients with higher heart rate, but with a fall of the slope in cases with extreme tachycardia. By dividing our study population on the basis of the most important clinical variables, this complex relation was evident only in patients at a more advanced stage of the disease. CONCLUSION: Our analysis confirms the strict relationship between heart rate and improvement with chronic metoprolol therapy in patients with DCM. This relation seems to be non-linear and is influenced by the severity of the disease.

[Bundle-branch reentry ventricular tachycardia induced by sinus beat]. / Tachicardia ventricolare da rientro branca a branca indotta da battito sinusale.

A spontaneous episode of bundle branch reentry ventricular tachycardia was recorded in a 50 year old man few weeks after operation for a severe aortic valve regurgitation. After surgery, the patient developed recurrent syncope and showed a bradycardia-dependent left bundle branch block and a HV interval of 70 ms. A bundle branch reentry ventricular tachycardia with left bundle branch block morphology, easily induced during premature ventricular stimulation, occurred spontaneously after the longest sinus cycle of a sequence conducted to the ventricles with a left bundle branch block morphology of the QRS complexes. During left bundle branch block an incomplete and concealed anterograde conduction along the left bundle branch was supposed to be present and its disappearance was considered the trigger mechanism of the spontaneous ventricular tachycardia. The negative results obtained with the signal-averaged ECG in our case support the concept that intramyocardial delay is not essential for this type of ventricular tachycardia.

Familial right ventricular dysplasia with biventricular involvement and inflammatory infiltration. Heart Muscle Disease Study Group.

The aetiology of right ventricular dysplasia/cardiomyopathy is presently unknown. A genetic background has been suggested, but myocarditis may play a part in its pathogenesis. Two familial cases of right ventricular dysplasia, one of whom had also a diagnosis of myocarditis, are reported. Both patients presented with ventricular arrhythmias. The father subsequently had a "flu-like" syndrome, heart failure, and biventricular dysfunction; "active" myocarditis was found at endomyocardial biopsy. Then the patient died suddenly. The daughter developed progressive biventricular dysfunction; then she was resuscitated from a cardiac arrest, and subsequently died suddenly. In both patients necropsy showed severe right ventricular atrophy and fibro-adipose substitution, associated with biventricular fibrosis. Inflammatory infiltration was also present in the first patient. This study shows the association of right ventricular dysplasia and myocarditis in the same family. These cases may represent a link between inherited and acquired ("inflammatory") forms of the disease.

Genetic factors in dilated cardiomyopathy.

Recent studies have demonstrated that genetic factors are likely to play a major role in the pathogenesis of idiopathic dilated cardiomyopathy (IDC). In clinical surveys, a familial trait has been demonstrated in 20 to 30% of idiopathic dilated cardiomyopathy patients (familial dilated cardiomyopathy). Molecular genetic studies have confirmed the clinical hypothesis of genetic heterogeneity in familial dilated cardiomyopathy, and are currently producing relevant advances in the understanding of this disease. The autosomal dominant form is considered to be the most frequent form of inherited idiopathic dilated cardiomyopathy. After the exclusion of a large series of candidate genes, the first familial dilated cardiomyopathy gene has been mapped to the long arm of chromosome 9. A second locus has been found on chromosome 1. Moreover, in two large families, characterized by a peculiar form of conduction delays and later development of myocardial dysfunction, the disease loci have been mapped to chromosome 1 and 3, respectively. The identification of the disease genes is in progress. In families with X-linked dilated cardiomyopathy, the disease gene has been identified as the dystrophin gene. The 5' end of the gene appears to be the critical region for the development of dilated cardiomyopathy without clinical evidence of muscle dystrophy. Furthermore, other cytoskeletal proteins, such as adhalin, could be involved in the pathogenesis of familial dilated cardiomyopathy. In familial right ventricular cardiomyopathy (or arrhythmogenic right ventricular dysplasia) characterized by isolated or prevalent right ventricular involvement, three different disease loci have been identified so far: two localized on the long arm of chromosome 14 and one on chromosome 1. The disease genes are still unknown and are currently under investigation. The study of the genetic factors at the molecular level is starting to elucidate the pathogenetic mechanisms of idiopathic dilated cardiomyopathy. These findings will also have relevant clinical and therapeutic implications.

Metoprolol in dilated cardiomyopathy: is it possible to identify factors predictive of improvement? The Heart Muscle Disease Study Group.

BACKGROUND: Some controlled clinical trials showed a beneficial effect of beta-blockers on symptoms, exercise tolerance, and left ventricular function in dilated cardiomyopathy. The purpose of this study was to investigate if there are clinical variables at baseline that could predict a favorable response to long-term metoprolol therapy. METHODS AND RESULTS: Since November 1987, 94 consecutive patients with dilated cardiomyopathy and left ventricular ejection fraction less than 0.40 were treated with metoprolol (mean final dosage, 136 +/- 32 mg) associated with tailored medical therapy with digitalis, diuretics, and angiotensin-converting enzyme inhibitors. Eighty-four surviving patients had a complete 2-year noninvasive follow-up period. Ten patients died or were transplanted before the final assessment. Improvement was defined according to a clinical score based on left ventricular ejection fraction (increase > or = 10 U), left ventricular end-diastolic diameter (decrease > or = 10%), regression of restrictive filling pattern, New York Heart Association functional class, exercise tolerance (increase > or = 2 minutes), and cardiothoracic ratio (decrease > or = 10%). According to these criteria, 48 patients (51.1%) were classified as improved. Multivariate analysis identified a group of patients with a history of mild hypertension (blood pressure between 140/90 and 170/100 mmHg) and significantly higher probability of improvement with longterm metoprolol (odds ratio [OR], 2.22; 95% confidence interval, 1.25-3.94; P = .007). Among the 71 patients with normal blood pressure (< 140/90 mmHg), heart rate in upright position (100 vs 75 beats/min: OR, 2; 95% confidence interval, 1.38-4.94; P = .003), left ventricular ejection fraction 0.20-0.33 versus less than 0.20 (OR, 4.72; 95% confidence interval, 1.06-21.04; P = .042), and New York Heart Association class I-II versus III-IV (OR, 2.74; 95% confidence interval, 0.97-7.75; P = .05) were significantly associated with a positive response to metoprolol. At baseline, both supine and upright heart rate were significantly higher in patients who improved, but heart rate in the upright position was the most significant predictor of improvement in patients with normal blood pressure at multivariate analysis. CONCLUSIONS: According to the authors' logit model, patients with a history of mild hypertension or with a higher resting heart rate, associated with controlled symptoms of heart failure (New York Heart Association class I-II) or moderate to severe left ventricular ejection fraction (range, 0.20-0.33) showed a remarkable probability of long-term (2-year) improvement on metoprolol.

A new locus for arrhythmogenic right ventricular dysplasia on the long arm of chromosome 14.

Familial arrhythmogenic right ventricular cardiomyopathy or dysplasia (ARVD) is an idiopathic heart muscle disease with an autosomal-dominant pattern of transmission, characterized by fibro-fatty replacement of the right ventricular myocardium and ventricular arrhythmias. Recently, linkage to the chromosome 14q23-q24 (locus D14S42) has been reported in two families. In the present study, three unrelated families with ARVD were investigated. According to strict diagnostic criteria, 13 of 37 members were considered to be affected. Linkage to the D14S42 locus was excluded. On the other hand, linkage was found in the region 14q12-q22 in all three families (cumulative two-point lod score is 3.26 for D14S252), with no recombination between the detected locus and the disease gene. With multipoint linkage analysis, a maximal cumulative lod score of 4.7 was obtained in the region between loci D14S252 and D14S257. These data indicate that a novel gene causing familial ARVD (provisionally named ARVD2) maps to the long arm of chromosome 14, thus supporting the hypothesis of genetic heterogeneity in this disease.