Sleep quality and quality of life in patients with hypertrophic cardiomyopathy.

OBJECTIVES: To evaluate clinical predictors of poor sleep quality and quality of life (QOL) in patients with hypertrophic cardiomyopathy (HCM). METHODS: Consecutive stable patients with HCM were evaluated for the risk of obstructive sleep apnea (OSA) by the Berlin Questionnaire, daytime sleepiness by the Epworth Sleepiness Scale, sleep quality by the Pittsburgh Sleep Questionnaire Index and QOL by the Minnesota Living with Heart Failure Questionnaire. Asymptomatic subjects without HCM were used as controls. RESULTS: We studied 84 patients with HCM and 42 controls who were similar with regard to gender (49 vs. 50% males), age [52 (38-62) vs. 47 (33-58) years] and body mass index (27 ± 4 vs. 27 ± 5). HCM diagnosis, high risk for OSA and female gender were independently associated with poor sleep quality in the entire population. Among patients with HCM, poor QOL was independently associated with poor sleep quality, New York Heart Association functional class and diuretic therapy. CONCLUSION: Poor sleep quality is very common in patients with HCM and may have a negative impact on the QOL, which in turn is an important marker of prognosis in patients with cardiomyopathies.

Value of real time three-dimensional echocardiography in patients with hypertrophic cardiomyopathy: comparison with two-dimensional echocardiography and magnetic resonance imaging.

UNLABELLED: Real time three-dimensional echocardiography (RT3DE) has been demonstrated to be an accurate technique to quantify left ventricular (LV) volumes and function in different patient populations. We sought to determine the value of RT3DE for evaluating patients with hypertrophic cardiomyopathy (HCM), in comparison with cardiac magnetic resonance imaging (MRI). METHODS: We studied 20 consecutive patients with HCM who underwent two-dimensional echocardiography (2DE), RT3DE, and MRI. Parameters analyzed by echocardiography and MRI included: wall thickness, LV volumes, ejection fraction (LVEF), mass, geometric index, and dyssynchrony index. Statistical analysis was performed by Lin agreement coefficient, Pearson linear correlation and Bland-Altman model. RESULTS: There was excellent agreement between 2DE and RT3DE (Rc = 0.92), 2DE and MRI (Rc = 0.85), and RT3DE and MRI (Rc = 0.90) for linear measurements. Agreement indexes for LV end-diastolic and end-systolic volumes were Rc = 0.91 and Rc = 0.91 between 2DE and RT3DE, Rc = 0.94 and Rc = 0.95 between RT3DE and MRI, and Rc = 0.89 and Rc = 0.88 between 2DE and MRI, respectively. Satisfactory agreement was observed between 2DE and RT3DE (Rc = 0.75), RT3DE and MRI (Rc = 0.83), and 2DE and MRI (Rc = 0.73) for determining LVEF, with a mild underestimation of LVEF by 2DE, and smaller variability between RT3DE and MRI. Regarding LV mass, excellent agreement was observed between RT3DE and MRI (Rc = 0.96), with bias of-6.3 g (limits of concordance = 42.22 to-54.73 g). CONCLUSION: In patients with HCM, RT3DE demonstrated superior performance than 2DE for the evaluation of myocardial hypertrophy, LV volumes, LVEF, and LV mass.

Aortic distensibility measured by pulse-wave velocity is not modified in patients with Chagas' disease.

BACKGROUND: Experimental studies demonstrate that infection with trypanosoma cruzi causes vasculitis. The inflammatory lesion process could hypothetically lead to decreased distensibility of large and small arteries in advanced Chagas' disease. We tested this hypothesis. METHODS AND RESULTS: We evaluated carotid-femoral pulse-wave velocity (PWV) in 53 Chagas' disease patients compared with 31 healthy volunteers (control group). The 53 patients were classified into 3 groups: 1) 16 with indeterminate form of Chagas' disease; 2) 18 with Chagas' disease, electrocardiographic abnormalities, and normal systolic function; 3) 19 with Chagas' disease, systolic dysfunction, and mild-to-moderate congestive heart failure. No difference was noted between the 4 groups regarding carotid-femoral PWV (8.4 +/- 1.1 vs 8.2 +/- 1.5 vs 8.2 +/- 1.4 vs 8.7 +/- 1.6 m/s, P = 0.6) or pulse pressure (39.5 +/- 7.6 vs 39.3 +/- 8.1 vs 39.5 +/- 7.4 vs 39.7 +/- 6.9 mm Hg, P = 0.9). A positive, significant, similar correlation occurred between PWV and age in patients with Chagas' disease (r = 0.42, P = 0.002), in controls (r = 0.48, P = 0.006), and also between PWV and systolic blood pressure in both groups (patients with Chagas' disease, r = 0.38, P = 0.005; healthy subjects, r = 0.36, P = 0.043). CONCLUSION: Carotid femoral pulse-wave velocity is not modified in patients with Chagas' disease, suggesting that elastic properties of large arteries are not affected in this disorder.

Benign outcome in a long-term follow-up of patients with hypertrophic cardiomyopathy in Brazil.

BACKGROUND: Selected patients with hypertrophic cardiomyopathy (HCM) have 3% to 4% annual mortality as compared to only 0.5% to 1.5% in nonselected patients. Our aim was to evaluate survival and prognostic factors in HCM in patients in a tertiary care center. METHODS: From 1980 to 1997, 214 patients were prospectively studied, with a mean follow-up of 7 years (range 1-25 years); there were 102 male and 112 female patients, aged 37 +/- 16 years (range 3-76 years). All patients had 12-lead electrocardiogram, 24-hour Holter monitor, and surface echocardiography. Univariate analysis was performed for known adverse factors such as young age, family history, syncope, functional class, atrial fibrillation, ventricular hypertrophy, left ventricular outflow tract obstruction, and nonsustained ventricular tachycardia. RESULTS: There were 22 deaths (10%), 15 directly related to HCM (sudden in 11). The cumulative survival rates were 94.5% at 5 years, 91% at 10 years, and 87.9% at 15 years. The annual mortality rate was 1%. Only New York Heart Association functional class III/IV and maximal ventricular wall thickness >30 mm were associated with HCM-related cardiac death. CONCLUSIONS: We concluded that even a referred population of HCM patients may have a relatively benign outcome. Prognosis is related to advanced functional class and degree of left ventricular hypertrophy.

Plasma amino-terminal pro-B-type natriuretic peptide quantification in hypertrophic cardiomyopathy.

BACKGROUND: Plasma B-type natriuretic peptide (BNP) is a sensitive functional marker in heart disease including hypertrophic cardiomyopathy (HCM). The utility of plasma amino-terminal pro-BNP (NT-proBNP) quantification in heart disease has been investigated, but there are no published data regarding this test in HCM. METHODS: Plasma NT-proBNP was assessed in 71 patients with HCM and in 40 healthy subjects. Symptomatic status was assessed according to the New York Heart Association classification. M-mode and Doppler echocardiographic data were obtained in all patients and healthy subjects to study their correlations and comparisons (Spearman and Mann-Whitney tests). RESULTS: Median NT-proBNP was 848 pg/mL in patients and 28 pg/mL in the control group (P < .0001). Patients in New York Heart Association functional class I/II had a median NT-proBNP of 669 pg/mL as compared with 3357 pg/mL for patients in class III/IV (P < .0001). Amino-terminal pro-BNP levels correlated positively with left atrial diameter (r = 0.40, P = .0005), septal thickness (r = 0.35, P = .002), and mitral flow velocity/mitral annulus velocity (E/Ea) ratio (r = 0.42, P < .0001). There was a weak correlation with obstruction (r = 0.23, P = .05), and a significant difference in the medians was observed between obstructive (1651 pg/mL) and nonobstructive (669 pg/mL) HCM groups (P = .01). Patients with Doppler E/Ea ratios > or = 10 had higher NT-proBNP levels than patients with E/Ea < 10 (P < .0001). Multivariate analysis showed that NT-proBNP correlated independently with left atrial diameter (P < .01), hypertrophy (P < .01), and E/Ea (P < .01). CONCLUSIONS: In HCM, plasma NT-proBNP levels are elevated and correlate positively with symptoms of heart failure, hypertrophy severity, and Doppler echocardiographic signs of left ventricular diastolic dysfunction. Further studies are necessary to assess the usefulness of the test in clinical practice and its role as a prognostic marker.

Relationships among exercise capacity, hypertrophy, and left ventricular diastolic function in nonobstructive hypertrophic cardiomyopathy.

AIM: The aim of this study was to analyze the relationships among exercise capacity (EC), hypertrophy, and diastolic function in nonobstructive hypertrophic cardiomyopathy (NOHCM). METHODS AND RESULTS: Twenty-seven patients with NOHCM were studied. Left ventricular hypertrophy (LVH) was determined by appropriate echocardiographic indexes. For diastolic function evaluation, the following were measured: the early (E) and late (A) waves, E/A, and deceleration time of E of the mitral flow; the systolic (S), diastolic (D), and atrial reversal (AR) waves, S/D, and the atrial systolic filling fraction of the pulmonary vein flow; and the early (Ea), late (Aa) waves, Ea/Aa, and E/Ea by tissue Doppler imaging. The difference between the duration of AR and A waves (DurAR - DurA), the peak VO2, and anaerobic threshold (AT) were also determined. In these patients, the E/Ea ratio was 8.9 +/- 3.2 and DurAR - DurA was 22.6 +/- 32.6 milliseconds. The peak VO2 and AT correlated with D (r = 0.55, P = .003 and .51, P = .007, respectively) and Ea/Aa (r = 0.56, P = .007 and .45, P = .03, respectively). There was no correlation between EC and LVH. CONCLUSIONS: Patients with NOHCM demonstrated evidences of elevated left ventricular (LV) end-diastolic pressure with normal filling pressure. EC compromise may be attributed to relaxation changes with inadequate filling of the left ventricle.

Effect of Losartan on left ventricular diastolic function in patients with nonobstructive hypertrophic cardiomyopathy.

In hypertrophic cardiomyopathy (HC), diastolic dysfunction of the left ventricle is a prominent feature caused by myocardial hypertrophy and fibrosis. Angiotensin II has trophic and profibrotic effects on the heart, and the blockade of angiotensin II receptors reverses hypertrophy and fibrosis in human cardiac diseases and in animal HC. This study investigated the short-term (6 months) effects of losartan 100 mg/day in 20 patients with nonobstructive HC, with an emphasis on left ventricular (LV) diastolic dysfunction, compared with 10 patients with HC who were not treated. At the final evaluation, significant changes were observed in the losartan group: a left atrial diameter decrease (p<0.0001), a tissue Doppler early (Ea) mitral annulus diastolic velocity increase (p=0.003) and an E/Ea ratio decrease (p=0.0002), and a significant decrease in plasma levels of the aminoterminal fragment of pro-brain natriuretic peptide (NT-pro-BNP) from a median of 860 to 606 pg/ml (p=0.001). A significant correlation was found between percentage changes in NT-pro-BNP and the E/Ea ratio from baseline to 6 months (r=0.61, p=0.002). In the 2 groups, echocardiographic LV wall and cavity measures did not change. In conclusion, in selected patients with nonobstructive HC, losartan during a 6-month period improved LV diastolic function.

Visualization of coronary arteries using intravenous contrast agent and real-time 3-dimensional echocardiography in a patient with hypertrophic cardiomyopathy.

Real-time 3-dimensional echocardiography is a recently developed imaging technique that provides unique information on spatial geometry in real time. We described an asymptomatic patient with hypertrophic obstructive cardiomyopathy for whom 3-dimensional echocardiography was performed after intravenous injection of perfluorocarbon-filled microbubbles. It resulted in enhancement of the left ventricular endocardial border delineation and myocardial perfusion in the hypertrophic septum. A clear visualization of the entire course of the left anterior descending coronary artery and its septal perforator branches was obtained. This case illustrates the potential of real-time 3-dimensional echocardiography to improve the anatomic evaluation of coronary arteries, especially when combined with contrast agents.

[Relation between left atrial dimension and exercise capacity in endomyocardial fibrosis]. / Relação do tamanho do átrio esquerdo com a capacidade de exercício na endomiocardiofibrose.

OBJECTIVE: To assess whether exercise capacity is related to left atrial dimension (LAD) in patients with biventricular endomyocardial fibrosis. METHODS: This study comprised 38 patients in sinus rhythm, with a mean age of 37.5 +/- 11.5 years (range, 11 to 59 years), 25 of whom were women. They were divided into 2 groups according to the NYHA functional class on hospital admission as follows: group A (12 patients) and group B (26 patients). All patients underwent cardiopulmonary exercise testing to determine their maximum oxygen consumption (VO2 max), and their left atrial dimension was determined on echocardiography. RESULTS: The VO2max values for groups A and B were 21.8 +/- 4.8 mL.kg(-1).min(-1) and 13.7 +/- 3.5 mL.kg(-1).min(-1), respectively, and the left atrial dimensions were 3.7 +/- 0.7 cm and 4.4 +/- 0.7 cm for groups A and B, respectively. A significant and inverse correlation was found between VO2max and LAD in the groups studied. CONCLUSION: The increase in left atrial dimension is associated with impairment in exercise capacity in patients with endomyocardial fibrosis. Our findings support the use of left atrial dimension to estimate a more complex and difficult to assess index of functional capacity, such as VO2max.

[Maximal functional capacity, ejection fraction, and functional class in Chagas cardiomyopathy. Are these indices related?]. / Capacidade funcional máxima, fração de ejeção e classe funcional na cardiomiopatia chagásica. Existe relação entre estes índices?

OBJECTIVE: Left ventricular ejection fraction (LVEF) and maximal functional capacity (VO2max) have both been shown to be related to a poor long-term survival in Chagas' disease patients. The aim of this study was to estimate the potential association of VO2max, LVEF, and NYHA functional class in patients with Chagas' disease cardiomyopathy. METHODS: One hundred four male patients, aged 40.3+/-9.0 years (range, 18 to 65), with a definite diagnosis of Chagas disease cardiomyopathy were studied. LVEF and VO2max were both classified into 3 degrees: LVEF 0.50 and VO2max < or = 10, 10 < VO2max < or = 20, and VO2max > 20 ml.kg(-1).min(-1), respectively. RESULTS: Thirty-one patients (29.8%) were in NYHA functional class II, 41 (39.4%) in functional class III, and 32 (30.8%) in functional class IV. The corresponding values of VO2max and LVEF for functional classes II, III, and IV were 21.5+/-4.0 ml.kg(-1).min(-1), 18.3+/-5.8 ml.kg(-1).min(-1), and 14.7+/-4.9 ml.kg(-1).min(-1) and 0.50+/-0.6, 0.35+/- 0.9, and 0.29+/-0.7, respectively. LVEF = < or = 0.30 and VO2max = < or = 10 ml.kg(-1).min(-1) were found in the majority of patients in NYHA functional class IV. Conversely, patients in functional class II were mostly those with LVEF > 0.50 as well as VO2max > 20 ml.kg(-1).min(-1). CONCLUSION: A convincingly good association exists between NYHA functional class, functional capacity and LVEF in patients with Chagas' disease cardiomyopathy. These data may be helpful in the management of heart failure in Chagas' disease patients.

[Quantitative assessment of left ventricular regional wall motion in endomyocardial fibrosis]. / Avaliação quantitativa da movimentação parietal regional do ventrículo esquerdo na endomiocardiofibrose.

OBJECTIVE: To analyze left ventricular (LV) regional wall motion in patients with endomyocardial fibrosis (EMF). METHODS: The study comprised 88 patients, 59 of the female sex, with a mean age of 39+/-13 years (range, 9 to 65) and with echocardiographic and angiographic evidence of left ventricular EMF. The intensity of fibrous tissue buildup on contrast cineventriculography was classified as mild, moderate, or severe. The overall left ventricular ejection fraction (LVEF) was determined by using the area-length method on ventriculography. The motion was measured in 100 equidistant chords perpendicular to the centerline drawn in the middle of the final diastolic and systolic contours and normalized to cardiac size. Five left ventricular segments were analyzed: A--apical; AL--anterolateral; AB--anterobasal; IA--inferoapical; IB--inferobasal. Abnormality was expressed in units of standard deviation of the mean motion in a normal population of reference, comprised of 103 patients with normal LV according to clinical and electrocardiographic data, and angiographic standards. RESULTS: Mean LVEF was 0.47+/-0.12. Fibrous tissue buildup in the left ventricle was mild in 12 patients, moderate in 40, and severe in 36. The regions with the poorest ventricular wall motion were A (-1.4+/-1.6 standard deviation/chords) and IA (-1.6+/-1.8 standard deviation/chords) compared with that in AB (-0.3+/-1.9 standard deviation/chords), AL (-0.5+/-1.8 standard deviation/chords) and IB (-0.9+/-1.3 standard deviation/chords). No relation was observed between the intensity of fibrous tissue buildup and regional ventricular wall motion. CONCLUSION: A change in LV regional wall motion exists in EMF, and it is independent of the intensity of fibrous tissue buildup qualitatively assessed. Nonuniform involvement of the LV should be considered when planning surgery for this disease.

[Research of markers for the genes of the heavy chain of cardiac beta-myosin and myosin binding protein C in relatives of patients with hypertrophic cardiomyopathy]. / Pesquisa de marcadores para os genes da cadeia pesada da beta-miosina cardíaca e da proteína C de ligação à miosina em familiares de pacientes com cardiomiopatia hipertrófica.

OBJECTIVE: To study the molecular markers for the genes of the heavy chain of cardiac beta-myosin and the myosin binding protein C in relatives of carriers of hypertrophic cardiomyopathy. METHODS: Twelve families who had anamnesis, physical exam, electrocardiogram, echocardiogram and blood collection for the genetic study through the chain reaction of polymerase. RESULTS: From the 227 relatives, 25% were ill-taken, with 51% men, with an average age of 35+/-19 (2 to 95) years old. The genetic analysis showed a connection with the gene of the cardiac b-myosin in a family and, in another, a connection with the gene of the myosin-binding protein C. In five families, the connections with the two genes were excluded; in two, the connection with the gene of the myosin-binding protein C, but for the b-myosin gene the results were non-conclusive; in two families, the results were non-conclusive for both genes and in one the connection for the b-myosin gene was excluded. The results were non-conclusive for the gene of the myosin-binding protein C. CONCLUSION: In our environment, other genes, different from those described in the literature, may prevail, or there are other genetic differences related to the origin of our population and/or environmental factors.

Clinical meaning of ascites in patients with endomyocardial fibrosis.

OBJECTIVE: To evaluate the clinical meaning of ascites and the main features of patients with ascites and endomyocardial fibrosis. METHODS: We studied 166 patients with endomyocardial fibrosis (mean age 37 years, 114 women) treated over the last 20 years. Ventriculography findings, surgery or necropsy confirmed the diagnosis in all patients. Most patients belonged to New York Heart Association Functional Class III/IV (134, 83.7%). Eighty-one (50.6%) had biventricular, 28 (17.5%) had right ventricular, and 51 (31.8%) had left ventricular involvement. During follow-up, 56 patients died. RESULTS: Ascites was present in 67 (41.8%) patients, and right ventricular involvement was present in 59 (88%). In the comparison between patients with or without ascites, those with ascites had higher mortality (49.2% and 24.7%, respectively). Patients with ascites had a higher incidence of edema (95% vs. 43%), hepatomegaly (5.8cm vs. 4.1cm), mean right atrium pressure (19.3 vs. 12mmHg), and final right ventricle diastolic pressure (18.7 vs. 12.9mmHg). Also, patients with ascites had a longer history of illness (5.1 and 3.9 years, respectively) and had atrial fibrillation more frequently (44.7% vs. 30.1%). CONCLUSION: Ascites was observed in less than 50% of cases of endomyocardial fibrosis and was associated with greater involvement of the right ventricle and with a longer duration of the disease, thus being a characteristic of a worse prognosis.

Myocardial fibrosis detected by cardiac CT predicts ventricular fibrillation/ventricular tachycardia events in patients with hypertrophic cardiomyopathy.

BACKGROUND: Myocardial fibrosis (MF) occurs in up to 80% of subjects with asymptomatic or mildly symptomatic hypertrophic cardiomyopathy (HCM) and can constitute an arrhythmogenic substrate for re-entrant, life-threatening ventricular arrhythmias in predisposed persons. OBJECTIVE: The aim was to investigate whether MF detected by delayed enhancement cardiac CT is predictive of ventricular tachycardia (VT) and fibrillation (VF) that require appropriate therapy by an implantable cardioverter defibrillator (ICD) in patients with HCM. METHODS: Twenty-six patients with HCM with previously (for at least 1 year) implanted ICD underwent MF evaluation by cardiac CT. MF was quantified by myocardial delayed enhanced cardiac CT. Data on ICD firing were recorded every 3 months after ICD implantation. Risk factors for sudden cardiac death in patients with HCM were evaluated in all patients. RESULTS: MF was present in 25 of 26 patients (96%) with mean fibrosis mass of 20.5 ± 15.8 g. Patients with appropriate ICD shocks for VF/VT had significantly greater MF mass than patients without (29.10 ± 19.13 g vs 13.57 ± 8.31 g; P = .01). For a MF mass of at least 18 g, sensitivity and specificity for appropriate ICD firing were 73% (95% CI, 49%-88%) and 71% (95% CI, 56%-81%), respectively. Kaplan-Meier curves indicated a significantly greater VF/VT event rate in patients with MF mass ≥18 g than in patients with MF <18 g (P = .02). In the Cox regression analysis, the amount of MF was independently associated with VF/VT in ICD-stored electrograms. CONCLUSION: The mass of MF detected by cardiac CT in patients with HCM at high risk of sudden death was associated with appropriate ICD firings.

Intramyocardial adrenergic activation in chagasic cardiomyopathy and coronary artery disease.

BACKGROUND: Myocardial norepinephrine is altered in left ventricular impairment. In patients with Chagas' cardiomyopathy (CC), this issue has not been addressed. OBJECTIVE: To determine the level of myocardial norepinephrine in patients with CC and compare it in patients with coronary artery disease, and to relate myocardial norepinephrine to left ventricular ejection fraction (LVEF). METHODS: We studied 39 patients with CC, divided into group 1: 21 individuals with normal LVEF and group 2: 18 individuals with decreased LVEF. Seventeen patients with coronary artery disease were divided into group 3: 12 individuals with normal LVEF and group 4: 5 individuals with decreased LVEF. Two-dimensional echocardiography was used to measure LVEF. Myocardial norepinephrine was determined by high-performance liquid chromatography. RESULTS: Myocardial norepinephrine in CC with and without ventricular dysfunction was 1.3±1.3 and 6.1±4.2 pg/µg noncollagen protein, respectively (p<0.0001); in coronary artery disease with and without ventricular dysfunction, it was 3.3±3.0 and 9.8±4.2 pg/µg noncollagen protein, respectively (p<0.0001). A positive correlation was found between LVEF and myocardial norepinephrine concentration in the patients with Chagas' cardiomyopathy (p<0.01, r = 0.57) and also in those with coronary artery disease (p<0.01, r=0.69). A significant difference was demonstrated between norepinephrine concentrations in patients with normal LVEF (groups 1 and 3; p = 0.0182), but no difference was found in patients with decreased LVEF (groups 2 and 4; p = 0.1467). CONCLUSION: In patients with Chagas' cardiomyopathy and normal global ejection fraction there is an early cardiac denervation, when compared to coronary artery disease patients.

[Study of mutations causing hypertrophic cardiomyopathy in a group of patients from Espirito Santo, Brazil]. / Estudo de mutações causadoras de cardiomiopatia hipertrófica em um grupo de pacientes no Espírito Santo, Brasil.

BACKGROUND: Hypertrophic cardiomyopathy (HC) is the most frequent cardiac hereditary disease, caused by mutations in sarcomere protein coding genes. Although more than 430 mutations have been identified in several continents and countries, there have been no reports of mutations in Brazil. OBJECTIVE: To carry out a genetic study to identify genetic mutations that cause HC in a group of patients in Espirito Santo, Brazil. METHODS: Using the SSCP technique, 12 exons from the three main genes involved in HC were studied: exons 15, 20, 21, 22 and 23 of the beta-myosin heavy chain gene (MYH7), exons 7, 16, 18, 22 and 24 of the myosin binding protein C gene (MYBPC3) and exons 8 and 9 of troponin T gene (TNNT2). RESULTS: 16 alterations were found, including two mutations, one of them possibly pathogenic in the MYBPC3 gene (p. Glu441Lys) and another pathogenic one, previously described in the TNNT2 gene (p.Arg92Trp), 8 rare sequence variations and 6 sequence variations with allelic frequency higher than 1% (polymorphisms). CONCLUSION: These data allow the conclusion that the genotyping of patients is feasible in our country. It is possible that the isolated p.Glu441Lys variant identified in exon 16 of the MYBPC3 gene is pathogenic, promoting a milder phenotype than that found when in association with other mutations. The p.Arg92Trp variant in the exon 9 of TNNT2 gene does not promote such a homogeneous phenotype as previously described and it can lead to severe hypertrophy.

[Myocardial fibrosis in patients with hypertrophic cardiomyopathy and high risk for sudden death]. / Fibrose miocárdica em pacientes com cardiomiopatia hipertrófica com alto risco para morte súbita cardíaca.

BACKGROUND: The stratification of risk for sudden death in hypertrophic cardiomyopathy (HCM) continues to be a true challenge due to the great heterogeneity of this disease's presentation, as most individuals remain asymptomatic during their entire lives and others present sudden death as first symptom. Recent studies have suggested that myocardial fibrosis may represent an important substrate for the malignant ventricular arrhythmias, that are responsible for the cases of sudden death related to this disease. OBJECTIVE: To assess the prevalence and quantification of myocardial fibrosis (MF) in hypertrophic cardiomyopathy (HCM) patients with implantablecardioverter - defibrillator (ICD) indicated due to their high risk or recovered from cardiac sudden death. METHODS: Twenty-eight HCM patients with ICD were submitted to multidetector computed tomography to assess myocardial fibrosis by delayed enhancement technique. RESULTS: Myocardial fibrosis was present in 96% of these HCM patients with (20.38 +/- 15.55 g) comprising 15.96 +/- 10.20% of the total myocardial mass. MF was observed in a significantly higher prevalence as compared to other classical risk factors for sudden death. CONCLUSION: It is possible to conclude that there is a high prevalence of myocardial fibrosis in hypertrophic cardiomyopathy patients with high-risk or recovered from cardiac sudden death, like those with clinical indication to implantable cardioverter -defibrillator. The higher prevalence of myocardial fibrosis in comparison to classical risk factors of worse prognosis raise the hypothesis that the myocardial fibrosis may be an important substrate in the genesis of lifethreatening arrhythmias in these high risk HCM population.

Obstructive sleep apnea is common and independently associated with atrial fibrillation in patients with hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is associated with arrhythmias and cardiovascular death. Left atrial enlargement and atrial fibrillation (AF) are considered markers for death due to heart failure in patients with HCM. Obstructive sleep apnea (OSA) is independently associated with heart remodeling and arrhythmias in other populations. We hypothesized that OSA is common and is associated with heart remodeling and AF in patients with HCM. METHODS: We evaluated 80 consecutive stable patients with a confirmed diagnosis of HCM by sleep questionnaire, blood tests, echocardiography, and sleep study (overnight respiratory monitoring). RESULTS: OSA (apnea-hypopnea index [AHI] > 15 events/h) was present in 32 patients (40%). Patients with OSA were significantly older (56 [41-64] vs 38.5 [30-53] years, P < .001) and presented higher BMI (28.2 +/- 3.5 vs 25.2 +/- 5.2 kg/m(2), P < .01) and increased left atrial diameter (45 [42-52.8] vs 41 [39-47] mm, P = .01) and aorta diameter (34 [30-37] vs 29 [28-32] mm, P < .001), compared with patients without OSA. Stepwise multiple linear regression showed that the AHI (P = .05) and BMI (P = .06) were associated with left atrial diameter. The AHI was the only variable associated with aorta diameter (P = .01). AF was present in 31% vs 6% of patients with and without OSA, respectively (P < .01). OSA (P = .03) and left atrial diameter (P = .03) were the only factors independently associated with AF. CONCLUSIONS: OSA is highly prevalent in patients with HCM and it is associated with left atrial and aortic enlargement. OSA is independently associated with AF, a risk factor for cardiovascular death in this population.

Leopard syndrome and hypertrophic cardiomyopathy: an association related to sudden death.

We describe an uncommon association between Leopard syndrome and hypertrophic cardiomyopathy in a 27-year-old woman, who was little symptomatic and came for sudden death risk stratification and prevention. She has a rare syndrome, whose symptoms are maculae over the body and abnormalities in eyes, genital organs, heart and in growth. Association of hypertrophic cardiomyopathy with sudden death risk factors determined the implantation of cardioverter-defibrillator (ICD) for primary prevention.