Mildly dilated congestive cardiomyopathy. Use of prospective diagnostic criteria and description of the clinical course without heart transplantation

Outcome and prognostic value of N-terminal pro-brain natriuretic peptide and high-sensitivity C-reactive protein in mildly dilated cardiomyopathy vs. dilated cardiomyopathy

AIMS

Mildly dilated cardiomyopathy (MDCM) was characterized as a subset of dilated cardiomyopathy (DCM) with systolic dysfunction and modest ventricular dilatation, of which the prognostic studies were limited. We aimed to compare the prognostic value of the N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hs-CRP) between MDCM and DCM.

METHODS AND RESULTS

We retrospectively included hospitalized patients diagnosed with DCM and a left ventricular ejection fraction ≤ 50% at Fuwai Hospital from 2006 to 2017. MDCM was defined as left ventricular end-diastolic diameter index (LVEDDi) ≤ 33 mm/m² in males and ≤34 mm/m² in females. A total of 640 patients (median age 49 years, 24.8% female) were included in this study. At baseline, 110 cases (17%) were categorized as MDCM and 529 cases (83%) as DCM. Of 282 patients who had follow-up echocardiograms ≥ 6 months, 7 MDCM patients (11.1%) evolved to DCM and 70 DCM patients (32.0%) recovered to MDCM by the change of LVEDDi. Compared with DCM, patients with baseline MDCM had lower composite risks of all-cause mortality, heart transplantation, and heart failure rehospitalization [adjusted hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.43-0.93, P = 0.019]. Both hs-CRP and NT-proBNP were independently associated with the composite endpoint in the overall cohort (hs-CRP: adjusted HR 1.07, 95% CI 1.00-1.15, P = 0.036; NT-proBNP: adjusted HR 1.11, 95% CI 1.02-1.22, P = 0.019). After a propensity-score matching between MDCM and DCM, higher NT-proBNP (above the median) was significantly associated with the outcome in DCM patients (HR 1.83, 95% CI 1.05-3.20, P = 0.034), but not in MDCM patients (HR 1.54, 95% CI 0.76-3.11, P = 0.227). On the contrary, higher hs-CRP (above the median) showed prognostic value for adverse events in MDCM patients (HR 3.19, 95% CI 1.52-6.66, P = 0.002), but not in DCM patients (HR 1.04, 95% CI 0.61-1.79, P = 0.88).

CONCLUSIONS

In patients with MDCM, although no evidence suggested the prognostic role of NT-proBNP, higher level of hs-CRP was associated with outcome, supporting the use of hs-CRP in risk stratification for patients with MDCM.

Multi-Modality Imaging in Dilated Cardiomyopathy: With a Focus on the Role of Cardiac Magnetic Resonance

Heart failure (HF) is recognized as a leading cause of morbidity and mortality worldwide. Dilated cardiomyopathy (DCM) is a common phenotype in patients presenting with HF. Timely diagnosis, appropriate identification of the underlying cause, individualized risk stratification, and prediction of clinical response to treatment have improved the prognosis of DCM over the last few decades. In this article, we reviewed the current evidence on available imaging techniques used for DCM patients. In this direction, we evaluated appropriate scenarios for the implementation of echocardiography, nuclear imaging, and cardiac computed tomography, and we focused on the primordial role that cardiac magnetic resonance (CMR) holds in the diagnosis, prognosis, and tailoring of therapeutic options in this population of special clinical interest. We explored the predictive value of CMR toward left ventricular reverse remodeling and prediction of sudden cardiac death, thus guiding the decisions for device therapy. Principles underpinning the use of state-of-the-art CMR techniques such as parametric mapping and feature-tracking strain analysis are also provided, along with expectations for the anticipated future advances in this field. We also attempted to correlate the evidence with clinical practice, with the intent to address questions on selecting the optimal imaging method for different indications and clinical needs. Overall, we recommend a comprehensive assessment of DCM patients at baseline and at follow-up intervals depending on the clinical status, with the addition of CMR as a second-line modality to other imaging techniques. We also provide an algorithm to guide the detailed imaging approach of the patient with DCM. We expect that future guidelines will upgrade their clinical recommendations for the utilization of CMR in DCM, which is expected to further improve the quality of care and the outcomes. This review provides an up-to-date perspective on the imaging of dilated cardiomyopathy patients and will be of clinical value to training doctors and physicians involved in the area of heart failure.

Speckle tracking echocardiography in hypokinetic non-dilated cardiomyopathy: comparison with dilated cardiomyopathy

Aims

Hypokinetic non‐dilated cardiomyopathy (HNDC), which is determined by impaired left ventricular (LV) systolic function despite normal LV size, has been categorized as a subgroup of dilated cardiomyopathy (DCM) spectrum. Lack of data regarding advanced echocardiographic data in this population motivated us to design the present study in order to assess LV myocardial deformation properties of HNDC patients against the ones with dilated left ventricle.

Methods and results

Thirty‐one HNDC patients and 23 DCM patients were enrolled in the study consecutively. Myocardial deformation parameters including global longitudinal strain, global circumferential strain, LV basal and apical rotation, LV twist, and LV mechanical dispersion were obtained with the use of two‐dimensional speckle tracking‐based methods in all patients. Left cardiac chamber volume was also measured using three‐dimensional HeartModel application. Patients with enlarged left ventricle tend to have lower LV ejection fraction. Comparing with HNDC group, DCM patients showed worse global circumferential strain (coefficient ± standard error 3.59 ± 0.94, P < 0.001) and LV mechanical dispersion (coefficient ± standard error 16.46 ± 7.09, P = 0.02) after regression analysis, while neither the global longitudinal strain nor the LV twist was not significantly different between two study population.

Conclusions

Left ventricular enlargement has a substantial effect on the circumferential strain and mechanical dispersion more than other deformation parameters that may play a role in the assumed poor prognosis of heart failure patients with dilated left ventricle.

How Left Ventricular Size Affects Severity of Disease and Long-term Prognosis in Patients with Severe Systolic Dysfunction?

BACKGROUND

We compared the severity of disease, heart failure (HF) rehospitalization and trend of changes over a 12-month follow-up in clinical and biochemical measurements between dilated cardiomyopathy (DCM) patients and those with left ventricular systolic dysfunction with normal LV size (NLVS). The existing definition of DCM failed to justify our observations in some clinical circumstances resulting in diagnostic and prognostic challenges.

METHODS

A total of 77 patients [52 (67.5%) male] including 40 patients in the NLVS group and 37 patients in the DCM group were enrolled and followed up for a median of 12 months [interquartile range, 11-14 months].

RESULTS

Mean left ventricular ejection fraction was statistically comparable between NLVS and DCM patients (22 ± 8% vs. 19 ± 6%, P = 0.08]. The New York Heart Association class was statistically comparable in both groups (P = 0.23). Laboratory measurements including hemoglobin, sodium, creatinine, uric acid, and NT-proBNP level were also statistically similar in both groups (all P > 0.05). During follow-up, HF rehospitalization occurred in 16 (76%) patients in NLVS and 5 (24%) patients in DCM groups (P = 0.009). Except for left ventricular ejection fraction which improved in both NLVS and DCM groups, no significant changes were observed in clinical (New York Heart Association class) and laboratory measurements during follow-up in both NLVS and DCM groups.

CONCLUSIONS

Our study showed that NLVS defines a group of systolic HF patients which not only did not have less severe disease than those with enlarged left ventricules (i.e., DCM), also had more HF rehospitalization. These NLVS patients also had steady clinical, laboratory, and echocardiographic profile during follow-up.

"Primary" dilated hearts

Dilated cardiomyopathy is part of the spectrum of heart failure which is a syndrome with certain morphological and functional characteristics. Although significant progress in the management of those patients has been achieved, seems that risk stratification and future treatments will be related to the specific pathological substrate.

Insights into mildly dilated cardiomyopathy: temporal evolution and long-term prognosis

AIMS

Mildly dilated cardiomyopathy (MDCM) has been proposed as a subtype of dilated cardiomyopathy (DCM) characterized by systolic dysfunction in the absence of significant LV dilatation. Few data on the characteristics and outcomes of MDCM patients are available. We sought to assess the main features and the long-term natural history of MDCM.

METHODS AND RESULTS

From 1988 to 2010 we analysed all DCM patients consecutively evaluated at our Institution. MDCM was defined as LVEF <45% and LV end-diastolic volume index (LVEDVI) ≤70 mL/m² in women and ≤89 mL/m² in men. Among a total population of 638 patients, 226 (35%) fulfilled the criteria for MDCM. Compared with the other patients, they presented features of a less advanced disease and an overall long-term lower rate of all-cause mortality/heart transplantation (D/HTx; total events = 209; 144 deaths, 65 HTx): D/HTx at 10 years 15% in MDCM vs. 30% in DCM (P < 0.001). However, throughout the follow-up, 55 MDCM patients (24%) evolved to DCM by increasing LVEDVI, consistently worsening their long-term prognosis. Among persistent MDCM patients, a restrictive filling pattern [hazard ratio (HR) 5.30; 95% confidence interval (CI) 2.34-12.01, P < 0.001] and non-sustained ventricular tachycardia (HR 2.21; 95% CI 1.003-5.11, P = 0.047), but not LVEF, were independently associated with D/HTx at multivariate analysis [time-dependent receiver operating characteristic (ROC) curve: area under the curve (AUC) 0.80, 95% CI 0.65-0.94, P = 0.003].

CONCLUSIONS

MDCM identifies a consistent subgroup of DCMs diagnosed in an earlier stage and presenting an apparent better evolution. However, some MDCMs evolve into DCM despite medical therapy, whereas persistent MDCMs with non-sustained ventricular arrhythmias and restrictive filling pattern are characterized by a very poor outcome.

Proposal for a revised definition of dilated cardiomyopathy, hypokinetic non-dilated cardiomyopathy, and its implications for clinical practice: a position statement of the ESC working group on myocardial and pericardial diseases

In this paper the Working Group on Myocardial and Pericardial Disease proposes a revised definition of dilated cardiomyopathy (DCM) in an attempt to bridge the gap between our recent understanding of the disease spectrum and its clinical presentation in relatives, which is key for early diagnosis and the institution of potential preventative measures. We also provide practical hints to identify subsets of the DCM syndrome where aetiology directed management has great clinical relevance.

Longitudinal quantile regression in the presence of informative dropout through longitudinal-survival joint modeling

We propose a joint model for a time-to-event outcome and a quantile of a continuous response repeatedly measured over time. The quantile and survival processes are associated via shared latent and manifest variables. Our joint model provides a flexible approach to handle informative dropout in quantile regression. A Monte Carlo expectation maximization strategy based on importance sampling is proposed, which is directly applicable under any distributional assumption for the longitudinal outcome and random effects. We consider both parametric and nonparametric assumptions for the baseline hazard. We illustrate through a simulation study and an application to an original data set about dilated cardiomyopathies.

Recurrence of left ventricular dysfunction in patients with restored idiopathic dilated cardiomyopathy

BACKGROUND

In some patients with nonischemic idiopathic dilated cardiomyopathy (DCM), left ventricular (LV) dysfunction improves spontaneously but can recur. The factors predicting recurrence of LV dysfunction in recovered idiopathic DCM are poorly defined. We investigated the clinical, echocardiographic, and laboratory variables affecting recurrence of LV dysfunction in patients who recovered from DCM.

HYPOTHESIS

The recurrence of LV dysfunction in recovered idiopathic DCM is impacted by clinical, echocardiographic, and laboratory variables.

METHODS

The study comprised 85 consecutively enrolled patients (62 males, age 57 ± 16 years) with DCM who achieved a restoration of LV systolic function. Patients were followed up for 50 ± 33 months after recovery from LV dysfunction without discontinuation of standard medication for heart failure with depressed ejection fraction. Clinical, echocardiographic, and laboratory variables were analyzed to identify factors independently associated with recurrence of LV dysfunction.

RESULTS

LV dysfunction recurred in 33 patients (23 males, age 64 ± 12 years). Univariate analysis revealed that age, duration from initial presentation to recovery time, diabetes, and LV end-diastolic dimension (LVEDD) at initial presentation were associated with recurrence of LV dysfunction. Multivariate analysis revealed that only age, diabetes, and LVEDD at initial presentation were independent predictors in patients who recovered from LV dysfunction.

CONCLUSIONS

The recurrence of LV dysfunction was significantly correlated with age, presence of diabetes, and LVEDD at initial presentation. Clinicians should consider maintenance of intensive care to patients who recovered from DCM with these factors.

Review and metaanalysis of the frequency of familial dilated cardiomyopathy

Several studies have investigated the frequency of familial dilated cardiomyopathy (FDC). However, no systematic review and meta-analysis on this topic are available. Therefore, using the PubMed, MEDLINE, Cochrane, and the ISI Web of Science databases, relevant reports published through December 2010 were identified. For the summation of prevalence findings, prevalence point estimates and 95% confidence intervals were computed using the logit transformation formula. An aggregate estimate of clinically confirmed FDC of 23% (95% confidence interval 0.17 to 0.31) was found. However, the prevalence rates reported across these studies varied widely, ranging from 2% to 65%, and the analysis showed very high heterogeneity (Q = 295, p <0.001, I(2) = 93%). Meta-regression analysis between logit event rate and year of publication explained 23% of between-study variance (p <0.05). Cumulative meta-analysis confirmed the influence of year of publication on the reported prevalence of FDC among the different studies. However, most of the observed heterogeneity may be explained by the fact that the various studies used different preselected criteria for the diagnosis of FDC. In conclusion, data obtained from trials performed using standardized criteria are needed to better define the true prevalence of FDC.

The impact of left ventricular size on response to cardiac resynchronization therapy

Patients with nondilated (NDCM) or severely dilated cardiomyopathies (SDCM) have been underrepresented in clinical trials of cardiac resynchronization therapy (CRT). We examined changes in left ventricular ejection fraction (LVEF) and survival in patients with NDCM or SDCM compared with those with traditionally studied moderately dilated cardiomyopathy.

METHODS

We evaluated 800 consecutive patients undergoing the original implantation of a biventricular pacemaker between January 2004 and August 2007. For inclusion, patients had a baseline and pre-CRT echocardiogram, an LVEF ≤40%, a US social security number, and New York Heart Association class II to IV symptoms on standard medical therapy. Patients with a follow-up echocardiogram >2 months after device implantation were included in an analysis of remodeling. Using multivariate models, the impact of baseline left ventricular end-diastolic diameter (LVEDD) on change in LVEF and all-cause mortality was assessed.

RESULTS

A total of 668 patients met inclusion criteria and were included in the assessment of mortality. Four hundred seventy-one had an appropriately timed follow-up echocardiogram and were included in the analysis of remodeling. Patients in all 3 groups realized improvements in LVEF (%) after CRT as follows: NDCM (n = 137; LVEDD ≤5.5 cm) 10.0 ± 12.7, P < .001; moderately dilated cardiomyopathy (n = 233; LVEDD 5.6-6.9 cm) 8.2 ± 11.3, P < .001; and SDCM (n = 101; LVEDD ≥7.0 cm) 5.4 ± 9.4, P < .001. In multivariate analysis, baseline LVEDD was inversely associated with change in LVEF (parameter estimate -3.13 ± 0.56, P < .001) and directly associated with increased all-cause mortality (hazard ratio 1.25 [1.05-1.47] P = .01).

CONCLUSION

Patients with NDCM and SDCM experience significant improvements in LVEF after CRT. The degree of baseline left ventricular dilatation before CRT is an important predictor of subsequent changes in LVEF and survival.

Clinical and genetic issues in dilated cardiomyopathy: a review for genetics professionals

Dilated cardiomyopathy (DCM), usually diagnosed as idiopathic dilated cardiomyopathy (IDC), has been shown to have a familial basis in 20-35% of cases. Genetic studies in familial dilated cardiomyopathy (FDC) have shown dramatic locus heterogeneity with mutations identified in >30 mostly autosomal genes showing primarily dominant transmission. Most mutations are private missense, nonsense or short insertion/deletions. Marked allelic heterogeneity is the rule. Although to date most DCM genetics fits into a Mendelian rare variant disease paradigm, this paradigm may be incomplete with only 30-35% of FDC genetic cause identified. Despite this incomplete knowledge, we predict that DCM genetics will become increasingly relevant for genetics and cardiovascular professionals. This is because DCM causes heart failure, a national epidemic, with considerable morbidity and mortality. The fact that early, even pre-symptomatic intervention can prevent or ameliorate DCM, coupled with more cost-effective genetic testing, will drive further progress in the field. Ongoing questions include: whether sporadic (IDC) disease has a genetic basis, and if so, how it differs from familial disease; which gene-specific or genetic pathways are most relevant; and whether other genetic mechanisms (e.g., DNA structural variants, epigenetics, mitochondrial mutations and others) are operative in DCM. We suggest that such new knowledge will lead to novel approaches to the prevention and treatment of DCM.

Prevalence and clinical characteristics of nondilated cardiomyopathy and the effect of atrial fibrillation

The treatment of patients with chronic heart failure and those with asymptomatic left ventricular (LV) dysfunction has focused primarily on patients with LV enlargement and a low ejection fraction (EF). Little attention has been paid to those with a normal chamber size and a low EF. We sought to examine the LV geometry and clinical characteristics in such patients with nondilated cardiomyopathy. Of 3,350 transthoracic echocardiograms performed during a 6-month period, 696 showed an EF of < or =0.45. The patients with an end-diastolic diameter of >56 mm, regional wall motion abnormalities, or valvular disease were excluded. Of the 696 patients, 98 met these criteria, and their medical records were reviewed. The average age was 71 +/- 14 years, and 56% were men. Common co-morbidities included hypertension in 52% and atrial fibrillation (AF) in 43%. Only 22% had disabling cardiac symptoms (functional class III or greater). The average end-diastolic dimension was 49 +/- 5 mm, and the EF was 34 +/- 8%. LV hypertrophic remodeling was present in 53%. A second echocardiogram (422 +/- 177 days after the baseline study) was available for 54 patients. The chamber size was unchanged, but the EF had increased from 33 +/- 8% to 40 +/- 14% (p <0.01). The improvement in EF was seen in the group with AF (33 +/- 6% to 44 +/- 15%, p <0.01) but not in those with normal sinus rhythm (33 +/- 9% to 37 +/- 12%, p = NS). In conclusion, 14% of patients with an EF of < or =0.45 had nondilated cardiomyopathy, often with LV hypertrophic remodeling and/or AF. An improvement in LV function can be expected in many patients with nondilated cardiomyopathy, particularly those with AF.

Predicting prognosis based on the shape of the left ventricular cavity in dilated cardiomyopathy: analysis using rate of improvement in the circle index

PURPOSE

To elucidate the relation between a quantitative measure of the shape of the left ventricular cavity, cardiac function, and prognosis in patients with dilated cardiomyopathy (DCM).

METHODS

The hearts of 20 healthy individuals and 18 patients with DCM were evaluated. Participants were aged 48.5 ± 5.0 years. On the basis of end-systolic four-chamber view echocardiograms, the endocardium of the left ventricle was traced and the resulting curve was segmented using 100 points. A line tangential to the curve was then drawn at each point, and the angle between two adjacent tangential lines was calculated. The deviation of these angles was designated as the circle index. The circle index and hemodynamic findings in patients with DCM were compared, and the rate of improvement in the circle index in these cases of DCM was determined. These patients were then placed into one of two groups: group R (11 patients), those with improvement rates of 10% or higher at time of discharge; and group NR (seven patients), those with rates less than 10%. Diuretic (furosemide) use, New York Heart Association (NYHA) classification, and readmission rate for the two groups were compared 2 years after discharge.

RESULTS

The circle index was 2.7 ± 0.9 in the DCM group and 17.5 ± 4.2 in the healthy group (P < 0.01). The circle index in the DCM group was correlated with pulmonary capillary wedge pressure (r(2) = 0.42). Use of furosemide was unchanged in group R 2 years after discharge, but had increased for all patients in group NR. All cases in group R were classified as NYHA I 2 years after discharge. In group NR, in contrast, although all cases were classified as NYHA I at discharge, five of seven cases had deteriorated to NYHA III-IV 2 years later and were readmitted to hospital.

CONCLUSION

There appears to be a quantifiable correlation between the circularity of the left ventricular cavity and the circle index. This suggests that rate of improvement after treatment for heart failure could predict prognosis in patients with DCM.

Clinical characteristics of 304 kindreds evaluated for familial dilated cardiomyopathy

BACKGROUND

Familial dilated cardiomyopathy (FDC) is dilated cardiomyopathy of unknown cause occurring in 2 or more closely related family members.

METHODS AND RESULTS

Members of 304 families suspected to have FDC were evaluated by family history (FH) and medical record review and were categorized as affected with idiopathic dilated cardiomyopathy (IDC), unaffected, unknown, or no data. Pedigrees were categorized with confirmed FDC, probable FDC, possible FDC or IDC based on strength of evidence. Of the 304 pedigrees, 125 were categorized as confirmed FDC, 48 were probable FDC, 72 were possible FDC, and 59 had sporadic, nonfamilial IDC. Numbers of living first- and second-degree family members, and median number of relatives available for FH was greatest with confirmed FDC, and diminished for probable and possible FDC, and IDC categories. LV dimensions increased and LV function worsened in index patients along the spectrum from confirmed FDC, probable FDC, possible FDC and IDC, and a greater proportion of IDC patients underwent heart transplant. However, the age of onset, duration of disease, the time to death or heart transplant, and most other findings were similar among the 4 categories.

CONCLUSION

Clinical characteristics of IDC and FDC are similar, precluding an FDC diagnosis from clinical features only.

Dilated versus nondilated cardiomyopathy in the elderly population treated with guideline-based medical therapy for systolic chronic heart failure

BACKGROUND

Although the process by which the left ventricular (LV) remodels in response to an injury generally leads to dilatation, in patients with heart failure (HF) the recognition of a small or mildly dilated left ventricle is not uncommon. We investigated the prevalence and the characteristics of elderly patients with traditional dilated and nondilated cardiomyopathy (CMP). We also assessed the response to the guideline-based medical therapy and the prognosis based on LV dilatation in this population.

METHODS AND RESULTS

We selected 243 patients >70 years of age with HF and LV ejection fraction <40% who underwent clinical and echocardiographic evaluations at baseline and after 12 months. They were subdivided into 2 groups according to baseline LV end-diastolic volume (LVEDV) (values < or =78 mL/m(2) identified nondilated CMP). Nondilated CMP was recognized in 64 patients (26%) who showed at baseline better clinical status, less severe mitral regurgitation, and higher LV ejection fraction than those with dilated CMP. At the final evaluation, favorable changes in clinical and echocardiographic parameters could be detected in both groups. The magnitude of these variations did not differ between the groups. The risk of hospitalization for worsening HF was 2.4-fold higher in patients with nondilated than dilated CMP. Mortality was 11% and 20%, respectively (P = .06). Statistical analysis revealed a direct, approximately linear relationship between LVEDV and outcomes in this population.

CONCLUSIONS

A total of 1 of 4 elderly patients with systolic HF had a nondilated left ventricle. These patients had a better clinical presentation than did counterparts with dilated left ventricles. After HF therapy is optimized, the likelihood of improvement is independent of LV size in this population, whereas the risk of death or worsening HF linearly increases with LV dilatation.

Long-Term Prognosis of Fulminant Myocarditis Rescued by Percutaneous Cardiopulmonary Support Device

BACKGROUND

The long-term prognosis and cardiac function of fulminant myocarditis treated with percutaneous cardiopulmonary support (PCPS) was compared with the outcome of those not treated with PCPS.

METHODS AND RESULTS

From 1991 to 2000, 14 patients with fulminant myocarditis (left ventricle ejection fraction (LVEF) < or =40%) were admitted to hospital. PCPS was necessary for treatment of shock in 8 (PCPS group), but not for the remaining 6 patients (non-PCPS group). In the PCPS group, 6 patients (75%) survived the critical phase and did not have any cardiac problems after discharge (range of follow-up period, 1.4-6.0 years). All patients in the non-PCPS group survived the acute phase; 1 patient had congestive heart failure 1.5 years after discharge, and another died from malignancy (follow-up period range, 2.2-9.4 years). Although the left ventricular ejection fraction (LVEF) of the PCPS group was significantly lower than that of the non-PCPS group in the acute phase, there was no significant difference in LVEF between the 2 groups in the chronic phase.

CONCLUSION

Patients who survive the acute phase crisis of acute myocarditis have a favorable long-term survival rate, whether or not mechanical support is used.

Natural history of dilated cardiomyopathy due to lamin A/C gene mutations

OBJECTIVES

We examined the prevalence, genotype-phenotype correlation, and natural history of lamin A/C gene (LMNA) mutations in subjects with dilated cardiomyopathy (DCM).

BACKGROUND

Mutations in LMNA have been found in patients with DCM with familial conduction defects and muscular dystrophy, but the clinical spectrum, prognosis, and clinical relevance of laminopathies in DCM are unknown.

BACKGROUND

A cohort of 49 nuclear families, 40 with familial DCM and 9 with sporadic DCM (269 subjects, 105 affected), was screened for mutations in LMNA using denaturing high-performance liquid chromatography and sequence analysis. Bivariate analysis of clinical predictors of LMNA mutation carrier status and Kaplan-Meier survival analysis were performed.

RESULTS

Mutations in LMNA were detected in four families (8%), three with familial (R89L, 959delT, R377H) and one with sporadic DCM (S573L). There was significant phenotypic variability, but the presence of skeletal muscle involvement (p < 0.001), supraventricular arrhythmia (p = 0.003), conduction defects (p = 0.01), and "mildly" DCM (p = 0.006) were predictors of LMNA mutations. The LMNA mutation carriers had a significantly poorer cumulative survival compared with non-carrier DCM patients: event-free survival at the age of 45 years was 31% versus 75% in non-carriers.

CONCLUSIONS

Mutations in LMNA cause a severe and progressive DCM in a relevant proportion of patients. Mutation screening should be considered in patients with DCM, in particular when clinical predictors of LMNA mutation are present, regardless of family history.

Clinical and epidemiological aspects of cardiomyopathies: a critical review of current knowledge

Five years after the second report of the WHO/ISFC Task Force on the definition and classification of cardiomyopathies (CM), a critical review of the matter appears well-timed. The need for a correct definition of myocardial diseases is emphasized by considering them the result of a 'direct' injury due to different known and unknown causes and not a consequence of ischemic disease or of pressure and/or volume overload. This is in order to eliminate terms like ischemic CM, valvular CM, and hypertensive CM, which are a source of confusion. The concept of myocardial injury is also reviewed. This should not only include the structural/organic macroscopic injury, but also the subcellular, ultrastructural, and molecular damage (mostly of genetic origin) of the contracting element proteins, of citosol, sarcolemma and cell membrane ion channels. As the myocardium is a complex structure, made of common fibers and of specific conduction tissue, injury may be clinically identified either by ventricular function impairment or by bioelectric function defects, i.e. tachyarrhythmias and/or bradyarrhythmias, which sometimes are the unique manifestation of the disease (arrhythmogenic CM, in the strict sense). On the basis of the morpho-functional alterations, CMs may be classified as dilated CM (which could be better identified as hypokinetic CM, referring to the functional aspect, because the morphologic aspect is not always present), hypertrophic CM, restrictive CM, and arrhythmogenic CM (including not only arrhythmogenic right ventricular CM, but also other forms, like the so-called arrhythmias of the 'apparently' healthy heart, due to 'occult' myocardial injury). Moreover, these forms may present in association, like mixed CM (dilated-arrhythmogenic, dilated-hypertrophic, etc.). From an etiologic point of view, it is advisable to maintain the distinction between specific CM, due to a known cause, and primary or idiopathic CM, including, together with sporadic forms of an unknown origin, familial forms of a genetic origin, depending on alterations of contractile or regulating functional proteins, when myocardial injury is the sole manifestation (idiopathic) of clinical picture. The most modern etiopathogenetic, pathophysiological, and clinical features of each form of CM are briefly described in order to suggest a complete definition of the disease and to state a clinical-epidemiological setting that encompasses the current knowledge.

Long-term prognosis of patients with mildly dilated cardiomyopathy

The long-term prognosis of patients with mildly dilated cardiomyopathy (MDCM) was investigated in 21 patients. MDCM was defined as left ventricular ejection fraction < or = 40% and left ventricular end-diastolic volume < or = 120 ml/m2 by left ventriculography. During a follow-up period of 6.8+/-3.7 years, there were 9 cardiac events (5 heart failure deaths, 2 sudden deaths, and 2 re-hospitalizations for heart failure). Only in the patients without cardiac events was there a significant decrease in left ventricular size (end-diastolic dimension decreased from 58+/-6 mm to 50+/-8 mm, p<0.001) and an improvement in systolic function (fractional shortening increased from 17+/-5% to 26+/-11%, p=0.007). However, left atrial dilation was observed in the patients with an event (from 39+/-5 mm to 43+/-5 mm, p=0.02). Based on proportional hazard analysis, left ventricular end-diastolic pressure and mean pulmonary artery pressure at diagnosis and left atrial dimension at the time of follow-up were significant predictors of poor outcome. A subset of patients with MDCM has impaired hemodynamics at diagnosis, left atrial dilation at follow-up and a poor prognosis, and must be followed carefully even if the left ventricular dilatation is mild.

Changes in myocardial cytoskeletal intermediate filaments and myocyte contractile dysfunction in dilated cardiomyopathy: an in vivo study in humans

AIM

To investigate in vivo the intermediate cytoskeletal filaments desmin and vimentin in myocardial tissues from patients with dilated cardiomyopathy, and to determine whether alterations in these proteins are associated with impaired contractility.

METHODS

Endomyocardial biopsies were performed in 12 patients with dilated cardiomyopathy and in 12 controls (six women with breast cancer before anthracycline chemotherapy and six male donors for heart transplantation). Biopsy specimens were analysed by light microscopy and immunochemistry (desmin, vimentin). Myocyte contractile protein function was evaluated by the actin-myosin in vitro motility assay. Left ventricular ejection fraction was assessed by echocardiography and radionuclide ventriculography.

RESULTS

Patients with dilated cardiomyopathy had a greater cardiomyocyte diameter than controls (p < 0.01). The increase in cell size was associated with a reduction in contractile function, as assessed by actin-myosin motility (r = -0.643; p < 0.01). Quantitative immunochemistry showed increased desmin and vimentin contents (p < 0.01), and the desmin distribution was disturbed in cardiomyopathy. There was a linear relation between desmin distribution and actin-myosin sliding in vitro (r = 0.853; p < 0.01) and an inverse correlation between desmin content and ejection fraction (r = -0.773; p < 0.02). Negative correlations were also found between myocardial vimentin content and the actin-myosin sliding rate (r = -0.74; p < 0.02) and left ventricular ejection fraction (r = -0.68; p < 0.01).

CONCLUSIONS

Compared with normal individuals, the myocardial tissue of patients with dilated cardiomyopathy shows alterations of cytoskeletal intermediate filament distribution and content associated with reduced myocyte contraction.

Echocardiographic findings in fulminant and acute myocarditis

OBJECTIVES

We sought to use echocardiography to assess the presentation and potential for recovery of left ventricular (LV) function of patients with fulminant myocarditis compared with those with acute myocarditis.

BACKGROUND

The clinical course of patients with myocarditis remains poorly defined. We have previously proposed a classification that provides prognostic information in myocarditis patients. Fulminant myocarditis causes a distinct onset of illness and severe hemodynamic compromise, whereas acute myocarditis has an indistinct presentation, less severe hemodynamic compromise and a greater likelihood of progression to dilated cardiomyopathy.

METHODS

Echocardiography was performed at presentation and at six months to test the hypothesis that fulminant (n = 11) or acute (n = 43) myocarditis could be distinguished morphologically.

RESULTS

Patients with both fulminant (fractional shortening 19 +/- 4%) and acute myocarditis (17 +/- 7%) had LV systolic dysfunction. Patients with fulminant myocarditis had near normal LV diastolic dimensions (5.3 +/- 0.9 cm) but increased septal thickness (1.2 +/- 0.2 cm) at presentation, while those with acute myocarditis had increased diastolic dimensions (6.1 +/- 0.8 cm, p < 0.01 vs. fulminant) but normal septal thickness (1.0 +/- 0.1 cm, p = 0.01 vs. fulminant). At six months, patients with fulminant myocarditis had dramatic improvement in fractional shortening (30 +/- 8%) compared with no improvement in patients with acute myocarditis (19 +/- 7%, p < 0.01 for interaction between time and type of myocarditis).

CONCLUSIONS

Fulminant myocarditis is distinguishable from acute myocarditis by echocardiography. Patients with fulminant myocarditis exhibit a substantial improvement in ventricular function at six months compared with those with acute myocarditis. Echocardiography has value in classifying patients with myocarditis and may provide prognostic information.

[The clinical practice guidelines of the Sociedad Española de Cardiología on cardiomyopathies and myocarditis]

Myocardial diseases are a extraordinarily heterogeneous group of processes that only have in common the fact that they involve heart muscle and that they cause a wide spectrum of myocardial dysfunction. The approach of the management and treatment of the cardiomyopathies is a continuous matter of discussion because the vast majority of alternatives in this field have not been based on the best scientific possible evidence and, since except for the case of heart failure associated with dilated cardiomyopathy. The majority of different options have not been studied by means of large (or even small) randomized trials. Nevertheless, this chapter has tried to provide the reader with different approaches on how to deal with important clinical problems in dilated, hypertrophic and restrictive cardiomyopathies, and in myocarditis as well. For this, we have utilized the most relevant information found coupled with our best clinical judgment, although we admit that many of the clinical recommendations can be controversial.

Familial dilated cardiomyopathy: evidence for genetic and phenotypic heterogeneity. Heart Muscle Disease Study Group

OBJECTIVES

This study was performed to evaluate the characteristics, mode of inheritance and etiology of familial dilated cardiomyopathy (FDC).

BACKGROUND

A genetic form of disease transmission has been identified in a relevant proportion of patients with dilated cardiomyopathy (DCM). Variable clinical characteristics and patterns of inheritance, and an increased frequency of cardiac antibodies have been reported. An analysis of FDC may improve the understanding of the disease and the management of patients.

METHODS

Of 350 consecutive patients with idiopathic DCM, 281 relatives from 60 families were examined. Family studies included clinical examination, electrocardiography, echocardiography and blood sampling. Of the 60 DCM index patients examined, 39 were attributable to FDC and 21 were due to sporadic DCM. Clinical features, histology, mode of inheritance and autoimmune serology were examined, molecular genetic studies were undertaken and the difference between familial and sporadic forms was analyzed.

RESULTS

Only a younger age (p = 0.0005) and a higher ejection fraction (p = 0.03) could clinically distinguish FDC patients from those with sporadic DCM. However, a number of distinct subtypes of FDC were identified: 1) autosomal dominant, the most frequent form (56%); 2) autosomal recessive (16%), characterized by worse prognosis; 3) X-linked FDC (10%), with different mutations of the dystrophin gene; 4) a novel form of autosomal dominant DCM with subclinical skeletal muscle disease (7.7%); 5) FDC with conduction defects (2.6%), and 6) rare unclassifiable forms (7.7%). The forms with skeletal muscle involvement were characterized by a restrictive filling pattern; the forms with isolated cardiomyopathy had an increased frequency of organ-specific cardiac autoantibodies. Histologic signs of myocarditis were frequent and nonspecific.

CONCLUSIONS

Familial dilated cardiomyopathy is frequent, cannot be predicted on a clinical or morphologic basis and requires family screening for identification. The phenotypic heterogeneity, different patterns of transmission, different frequencies of cardiac autoantibodies and the initial molecular genetic data indicate that multiple genes and pathogenetic mechanisms can lead to FDC.

Anthracycline-induced cardiomyopathy

Anthracycline cardiomyopathy is less frequently encountered nowadays, due to the well-recognised dose limitations and cardiac monitoring protocols used by chemotherapy centres. However, it is a condition that will persist due to the sensitivity of some patients to these drugs and the necessity for large doses to be used for certain individuals. We have demonstrated the benefit of angiotensin-converting enzyme inhibitor therapy and would consider introducing these compounds at the earliest opportunity. The use of probucol and vitamins as antioxidants capable of preventing the onset of cardiomyopathy in humans appears to require further investigation but may significantly reduce the incidence of this condition in the future.

Long-term survival in patients with mild or moderate impairment of left ventricular contractility during routine diagnostic left ventriculography

Long-term survival in patients with mild to moderate impairment of left ventricular contractility in the absence of coronary artery disease has not been studied extensively but the prognosis is assumed to be good. One hundred sixty-eight patients with angiographic evidence of mild or moderate impairment of left ventricular contractility and no other significant cardiac disease at the time of routine diagnostic cardiac catheterization were studied to determine long-term survival and event-free survival. Clinical characteristics, electrocardiograms, chest X-rays, laboratory data, and hemodynamics including end-diastolic volume, end-systolic volume, stroke volume, ejection fraction, and regional wall motion at the time of catheterization were examined. Patients with moderate impairment were more likely to have dyspnea (P = 0.005) and an abnormal electrocardiogram (P = 0.006) than patients with mild impairment. Mean ejection fraction was 57% (P = 0.0001 vs. normal) in patients with mild impairment and was 47% (P = 0.0001 vs. normal) in patients with moderate impairment. Wall motion studies showed impairment to be generalized and more significantly abnormal in patients with moderate impairment. Survival at a mean of 138 months could be determined in 162 of the 168 patients (96%). Fourteen year actuarial survival was 92% for patients with mild impairment compared to 75% for patients with moderate impairment (P = 0.01). Long-term prognosis is good in patients found to have mild generalized impairment at the time of routine diagnostic cardiac catheterization. In patients with moderate impairment, closer follow-up to prevent arrhythmia and the onset of congestive heart failure appears to be warranted.

Outer limits of the athlete's heart, the effect of gender, and relevance to the differential diagnosis with primary cardiac diseases

Two concepts from pathologic descriptions of myocardial hypertrophy in trained individuals merit consideration: (1) The heart of the trained athlete can be twice the normal size, but histologic structure remains intact, and (2) the weight of the trained heart does not usually surpass the limit of 500 g, defined as the critical heart weight. Even though this threshold cannot be accepted dogmatically, the concept of an upper limit for physiologic cardiac remodeling is nevertheless relevant to the clinical question of distinguishing extreme expressions of athlete's heart from primary pathologic conditions. This morphologic distinction depends on whether the magnitude of cardiac remodeling in athletes exceeds that expected as a result of athletic conditioning alone. There has also been a great interest in understanding the impact that types of athletic conditioning and gender have on defining the upper limits to which such physiologic hypertrophy may extend.

Predictive value of left ventricular response to exercise in patients with dilated cardiomyopathy--assessment by radionuclide ventriculography

The objective of this study was to determine noninvasively the likelihood of recovery of the left ventricular ejection fraction (LVEF) in patients with dilated cardiomyopathy (DCM) verified by radionuclide ventriculography. Twenty patients with DCM were classified into two groups according to the LVEF by M-mode echocardiographic findings two years after ventriculographic examination. The LVEF recovered to > or = 50% in 10 patients (Group A), while it was sustained at < 50% in 10 patients (Group B). The clinical features of each group were compared, based on results of physical examination, radionuclide ventriculography, and other diagnostic tests performed on their referral to hospital. Only the systolic blood pressure differed significantly between the two groups, being slightly, but significantly, increased in Group A over that in Group B (P < 0.05). LVEF at rest by radionuclide did not differ (Group A: 31.5 +/- 10.3% vs Group B: 26.5 +/- 9.4%). Peak exercise EF-EF at rest (peak delta EF) in Group A was apparently increased (3.4 +/- 4.0%), while that in Group B was decreased (-4.4 +/- 5.2%). The positive peak delta EF had a highly predictive value of 90% for patients with DCM whose LVEF will recover to more than 50%. The recovery EF-EF at rest did not differ significantly between groups (Group A: 8.4 +/- 4.7 vs Group B: 3.9 +/- 2.3, P < 0.05). Other clinical parameters such as functional class, cardiothoracic ratio, LVEF by echocardiography, cardiac index by Swan-Ganz catheter examination, and histologic examination of biopsied endocardium were indistinguishable in the two groups. The authors conclude that peak delta EF of radionuclide ventriculography on exercise indicates a preservation of LVEF and predicts a good clinical recovery in patients with DCM.

Cell-mediated cytotoxicity in hearts with dilated cardiomyopathy: correlation with interstitial fibrosis and foci of activated T lymphocytes

OBJECTIVES

The purpose of this study was to investigate the expression of perforin and T-cell intracellular antigen-1, two crucial components of lymphocyte-mediated cytotoxicity, in endomyocardial biopsies from patients with idiopathic dilated cardiomyopathy.

BACKGROUND

Previous reports have demonstrated the presence of myocardial interstitial fibrosis and increased infiltrating lymphocytes in patients with dilated cardiomyopathy. However, the pathogenic significance of these lymphocytic infiltrates remains unclear.

METHODS

Endomyocardial biopsies from 134 patients with idiopathic dilated cardiomyopathy were histologically and immunohistologically analyzed. Monoclonal antibodies against diverse T-lymphocyte antigens, perforin and T-cell intracellular antigen-1 were used with the highly sensitive avidin-biotin complex technique. Positive cells were counted in at least 10 high power field.

RESULTS

Perforin and T-cell intracellular antigen-1 were immunohistologically detected in all biopsies. Immunoreactivity was restricted to the cytoplasm and was granular in nature, indicating specific staining of cytoplasmic granules. Correlations were established between the expression of perforin and T-cell intracellular antigen-1 and the abundance of foci of various T-lymphocyte subpopulations and, most importantly, the degree of interstitial fibrosis on routine histologic examination (p = 0.015).

CONCLUSIONS

Cytotoxic activity is clearly present in endomyocardial biopsies from patients with idiopathic dilated cardiomyopathy. Local activation-that is, focal accumulation of T lymphocytes-seems to be important for the generation of lymphocyte-mediated cytotoxicity. The interstitial fibrosis commonly seen in dilated cardiomyopathy may be caused by cytotoxic T-lymphocyte damage to the myocardium.

Aortic valve endocarditis in an acutely rejecting orthotopic heart transplant recipient

Infective endocarditis is an infrequent but serious complication in heart transplant recipients. We report successful treatment for this serious complication.

Dobutamine stress ultrasonic myocardial tissue characterization in patients with dilated cardiomyopathy

Although acoustic properties of the myocardium are different between patients with cardiomyopathy and normal subjects, the frequency of the abnormal properties in patients with cardiomyopathy is unknown. We assessed the frequency of abnormal acoustic properties of the myocardium detectable with integrated backscatter in patients with cardiomyopathy and attempted more sensitive ultrasonic tissue characterization by combining dobutamine stress testing in patients with cardiomyopathy with apparently normal acoustic properties of the myocardium at rest. The magnitude of cyclic variation of integrated backscatter and calibrated myocardial integrated backscatter at end diastole were measured in 36 normal subjects and 40 patients with dilated cardiomyopathy. Either one of the integrated backscatter parameters was abnormal in 30 of 40 patients with cardiomyopathy. Dobutamine stress ultrasonic tissue characterization was performed in 10 patients with cardiomyopathy with normal values of both integrated backscatter parameters and 10 normal subjects. Calibrated myocardial integrated backscatter did not change during dobutamine infusion in any subject. The magnitude of cyclic variation in integrated backscatter increased in normal subjects but did not change in patients with cardiomyopathy despite a comparative associated increase in the systolic wall thickening during dobutamine infusion. Abnormal acoustic properties are detectable at rest with myocardial integrated backscatter about in three quarters of patients with cardiomyopathy. A combination of dobutamine stress testing would provide more sensitive ultrasonic myocardial tissue characterization and may make it possible to detect subtle changes in the acoustic properties of the myocardium in patients with dilated cardiomyopathy. Therefore dobutamine stress ultrasonic tissue characterization may detect mild dilated cardiomyopathy.

Familial dilated cardiomyopathy

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Discordance in degree of right and left ventricular dilation in patients with dilated cardiomyopathy: recognition and clinical implications

OBJECTIVES

The purpose of the present study was to assess the influence of variations in the relative degree of dilation of left and right ventricular chambers on the clinical outcome of patients with dilated cardiomyopathy.

BACKGROUND

Dilated cardiomyopathy, a primary myocardial disease characterized by ventricular dilation and systolic dysfunction, is generally associated with a poor prognosis. However, considerable variability has been observed in the clinical course and the morphologic and hemodynamic features in individual patients.

METHODS

We evaluated 67 consecutive patients with dilated cardiomyopathy and without evidence of ischemic or primary valvular heart disease. On the basis of diastolic ventricular chamber area measurements obtained by echocardiography, patients were classified into two groups: 38 patients with a relatively equal degree of left and right ventricular dilation (LV congruent to RV) and 29 patients with predominant and disproportionate dilation of the left ventricle (LV > RV).

RESULTS

The 67 patients ranged in age from 19 to 81 years (mean 56); 49 (73%) were male. The two subsets of patients with dilated cardiomyopathy did not differ with regard to age, left ventricular diastolic dimension, wall thickness and mass or ejection fraction. However, patients in the LV congruent to RV group showed more severe mitral and tricuspid regurgitation by Doppler echocardiography than did those in the LV > RV group (p = 0.01 for mitral and 0.004 for tricuspid regurgitation). Over the follow-up period of 2 to 60 months (mean 28), there were 19 deaths. Survival in the LV > RV group was significantly better than in the LV congruent to RV group (p = 0.03).

CONCLUSIONS

Patients with dilated cardiomyopathy represent a heterogeneous group with regard to both clinical outcome and the relative degree of left and right ventricular chamber dilation. Patients in the LV > RV subset appear to have better overall survival and less severe mitral and tricuspid regurgitation than do patients in the LV congruent to RV subset. Longitudinal studies are needed to determine whether these morphologic subsets in fact represent a continuum within the disease spectrum of dilated cardiomyopathy.

The spectrum of left ventricular size in dilated cardiomyopathy: clinical correlates and prognostic implications. SPIC (Italian Multicenter Cardiomyopathy Study) Group

To address the issues of variability and prognostic role of left ventricular dimensions in dilated cardiomyopathy (DCM), 144 patients with DCM were studied. They were arbitrarily assigned to two groups according to an echocardiographic left ventricular end-diastolic diameter index < or = 15% (45 patients with mildly dilated cardiomyopathy) and above 15% (99 patients with typically dilated cardiomyopathy) of the upper normality range. Among the patients with mildly dilated cardiomyopathy, there were more men (89% vs 66%; p < 0.01). This group of patients also had a greater prevalence of atrial fibrillation (22% vs 3%; p < 0.001) higher left ventricular fractional shortening (15 +/- 6% vs 13 +/- 5%; p < 0.05), higher ejection fraction (28 +/- 8% vs 24 +/- 8%; p < 0.01), and a lower exercise tolerance (5 +/- 2 MET vs 6 +/- 2 MET; p < 0.05). At the time of follow-up examination (30 +/- 15 months), event-free survival was not significantly different between patients with mildly dilated cardiomyopathy and those with typically dilated cardiomyopathy. Pulmonary capillary wedge pressure (p < 0.001) and left atrial dimension index (p < 0.01) were significant predictors of prognosis as determined by Cox multivariate analysis. Minimal or mild ventricular dilatation is not uncommon in DCM, and it identifies a heterogenous group of patients--some who are in the early stages of disease and others with severe pump dysfunction and persistently small hearts. Ventricular dilatation is not an independent predictor of prognosis.

Decreased concentration of myofibrils and myofiber hypertrophy are structural determinants of impaired left ventricular function in patients with chronic heart diseases: a multiple logistic regression analysis

OBJECTIVES

The aim of this study was to perform a multiple logistic regression analysis to identify independent structural determinants of impaired left ventricular function.

BACKGROUND

The association between contractile failure and structural alterations of the myocardium has been demonstrated in several studies, and multiple interactions between myocardial structure and cardiac performance are likely.

METHODS

Morphometric data assessed from 130 left ventricular biopsy specimens were analyzed. The endomyocardial specimens were obtained from 57 patients with normal coronary arteries (17 with normal left ventricular ejection fraction and 40 with impaired left ventricular function [dilated cardiomyopathy]), 15 patients with hypertrophic cardiomyopathy and 32 patients with aortic valve disease. Transmural biopsy specimens were assessed in 6 donor hearts before heart transplantation and in 20 patients with left anterior descending coronary artery disease whose specimens were obtained from the left ventricular anterior wall during aortocoronary bypass surgery. Global or regional left ventricular function was evaluated from left cineventriculograms. The volume fraction of cardiac fibrous tissue, intracellular volume fraction of myofibrils, volume fraction of myofibrils related to myocardial tissue (including fibrosis) and myofiber diameters were determined from semithin sections of the biopsy specimens with the use of light microscopic morphometry.

RESULTS

Multiple logistic regression analysis revealed decreased volume fraction of myofibrils (p < 0.005) and increased fiber diameter (p < 0.002) as independent determinants of impaired left ventricular function.

CONCLUSIONS

These data indicate that, independent of the underlying heart disease, both decreased concentration of contractile proteins and myocyte hypertrophy are independently associated with impaired left ventricular function.