Relation between marked changes in left ventricular outflow tract gradient and disease progression in hypertrophic cardiomyopathy

Impact of cibenzoline treatment on left ventricular remodelling and prognosis in hypertrophic obstructive cardiomyopathy

Aims

This study aimed to elucidate the long‐term effect of cibenzoline therapy on cardiovascular complications and prognosis in patients with hypertrophic obstructive cardiomyopathy (HOCM).

Methods and results

Eighty‐eight patients with HOCM were treated with cibenzoline (Group A), and 41 patients did not receive cibenzoline (Group B). The changes in left ventricular (LV) remodelling, incidences of cardiovascular complications and deaths, were examined. The mean follow‐up period was 15.8 ± 5.6 years in Group A and 17.8 ± 7.2 years in Group B. In Group A, the LV pressure gradient (LVPG) decreased immediately after treatment, and the reduction was maintained throughout the study. In Group B, the LVPG decreased gradually according to the deterioration of LV function. LV reverse remodelling was confirmed in Group A, and LV remodelling advanced in Group B. In Group A, the incidence of each cardiovascular complication was <10%. Only one patient experienced LV heart failure (LVHF). LVHF incidence and atrial fibrillation were higher in Group B than those in Group A (P < 0.0001). The incidence of death was 20.5% in Group A and 90.2% in Group B (P < 0.0001). The most frequent cause of death was sudden cardiac death (SCD) (38.9%) in Group A and LVHF (67.6%) in Group B. The incidence of SCD showed no significant difference between the two groups. The cumulative cardiac survival rate was higher in Group A than that in Group B (P < 0.0001).

Conclusions

Cibenzoline treatment significantly reduced all cardiovascular complications and death due to LVHF and may be a promising treatment in patients with HOCM.

Left Ventricular Remodeling in Hypertrophic Cardiomyopathy: An Overview of Current Knowledge

While most patients with hypertrophic cardiomyopathy (HCM) show a relatively stable morphologic and clinical phenotype, in some others, progressive changes in the left ventricular (LV) wall thickness, cavity size, and function, defined, overall, as “LV remodeling”, may occur. The interplay of multiple pathophysiologic mechanisms, from genetic background to myocardial ischemia and fibrosis, is implicated in this process. Different patterns of LV remodeling have been recognized and are associated with a specific impact on the clinical course and management of the disease. These findings underline the need for and the importance of serial multimodal clinical and instrumental evaluations to identify and further characterize the LV remodeling phenomenon. A more complete definition of the stages of the disease may present a chance to improve the management of HCM patients.

Liquid-liquid phase separation and extracellular multivalent interactions in the tale of galectin-3

Liquid-liquid phase separation (LLPS) explains many intracellular activities, but its role in extracellular functions has not been studied to the same extent. Here we report how LLPS mediates the extracellular function of galectin-3, the only monomeric member of the galectin family. The mechanism through which galectin-3 agglutinates (acting as a “bridge” to aggregate glycosylated molecules) is largely unknown. Our data show that its N-terminal domain (NTD) undergoes LLPS driven by interactions between its aromatic residues (two tryptophans and 10 tyrosines). Our lipopolysaccharide (LPS) micelle model shows that the NTDs form multiple weak interactions to other galectin-3 and then aggregate LPS micelles. Aggregation is reversed when interactions between the LPS and the carbohydrate recognition domains are blocked by lactose. The proposed mechanism explains many of galectin-3’s functions and suggests that the aromatic residues in the NTD are interesting drug design targets.

Galectin-3 consists of an unstructured N-terminal domain (NTD) and a structured carbohydrate-recognition domain and agglutinates neutrophils and glycosylated molecules in the extracellular milieu. Here the authors combine biophysical and biochemical experiments with NMR measurements and show that the galectin-3 NTD undergoes liquid-liquid phase separation (LLPS) and agglutinates other molecules through this process.

Alcohol Septal Ablation to Reduce Heart Failure

Hypertrophic cardiomyopathy is a commonly encountered inheritable cardiac disorder with variable phenotypic expression. Although most patients will have no or mild symptoms, 10% will develop heart failure symptoms refractory to medical management. This article discusses the mechanisms through which hypertrophic cardiomyopathy induces heart failure and how alcohol septal ablation can reverse each of these mechanisms to lead to clinical improvement.

Impact of adverse left ventricular remodeling on sudden cardiac death in patients with hypertrophic cardiomyopathy

BACKGROUND

Adverse left ventricular (LV) remodeling predicts heart failure symptoms and overt LV dysfunction in patients with hypertrophic cardiomyopathy (HCM), but its influence on the occurrence of sudden cardiac death (SCD) is unknown. The aim of this study was to investigate the effect of adverse LV remodeling on SCD risk in patients with HCM.

HYPOTHESIS

Adverse LV remodeling increases SCD in HCM patients.

METHODS

This study included 41 patients with HCM who experienced SCD; each case was matched with 3 controls based on age, gender, and time of first contact. In this population of 164 patients, predictors of SCD were identified using univariable and multivariable logistic regression and expressed as odds ratio (OR) with 95% confidence interval (CI).

RESULTS

Baseline characteristics, such as New York Heart Association (NYHA) class, systolic and diastolic left ventricular function, left ventricular wall thickness, left atrial size, atrial fibrillation, and established risk factors for SCD were similar in cases and controls. Independent predictors of SCD during follow-up (median follow-up, 7.7 ± 6.5 years) were: increase in NYHA class (OR: 8.7 [95% CI: 2.5-30.5], P = 0.001), decrease of fractional shortening (per % decrease, OR: 1.09 [95% CI: 1.03-1.14], P = 0.001), and decrease of diastolic function (OR: 3.5 [95% CI: 1.2-10.2], P = 0.02).

CONCLUSIONS

This study shows that SCD risk in HCM increases when adverse remodeling occurs. Because cases and controls were similar at baseline, these findings emphasize the importance of vigilant follow-up of HCM patients and could aid clinical decision making concerning implantable cardioverter-defibrillator implantation, especially in patients with moderate risk for SCD.

The 50-year history, controversy, and clinical implications of left ventricular outflow tract obstruction in hypertrophic cardiomyopathy from idiopathic hypertrophic subaortic stenosis to hypertrophic cardiomyopathy: from idiopathic hypertrophic subaortic stenosis to hypertrophic cardiomyopathy

Dynamic obstruction to left ventricular (LV) outflow was recognized from the earliest (50 years ago) clinical descriptions of hypertrophic cardiomyopathy (HCM) and has proved to be a complex phenomenon unique in many respects, as well as arguably the most visible and well-known pathophysiologic component of this heterogeneous disease. Over the past 5 decades, the clinical significance attributable to dynamic LV outflow tract gradients in HCM has triggered a periodic and instructive debate. Nevertheless, only recently has evidence emerged from observational analyses in large patient cohorts that unequivocally supports subaortic pressure gradients (and obstruction) both as true impedance to LV outflow and independent determinants of disabling exertional symptoms and cardiovascular mortality. Furthermore, abolition of subaortic gradients by surgical myectomy (or percutaneous alcohol septal ablation) results in profound and consistent symptomatic benefit and restoration of quality of life, with myectomy providing a long-term survival similar to that observed in the general population. These findings resolve the long-festering controversy over the existence of obstruction in HCM and whether outflow gradients are clinically important elements of this complex disease. These data also underscore the important principle, particularly relevant to clinical practice, that heart failure due to LV outflow obstruction in HCM is mechanically reversible and amenable to invasive septal reduction therapy. Finally, the recent observation that the vast majority of patients with HCM have the propensity to develop outflow obstruction (either at rest or with exercise) underscores a return to the characterization of HCM in 1960 as a predominantly obstructive disease.

Dilated-Hypokinetic Evolution of Hypertrophic Cardiomyopathy

OBJECTIVES

This study sought to investigate the incidence, risk factors, and prognosis of dilated-hypokinetic evolution in a large cohort of patients with hypertrophic cardiomyopathy (HCM) followed up at a cardiology center serving both the pediatric and the adult population.

BACKGROUND

The available data on this evolution of HCM mainly regards prevalence (rather than incidence) in adults, with very little being known about the pediatric population.

METHODS

A total of 222 consecutive HCM patients (65% men, 19% < or =18 years old) were prospectively evaluated for a mean follow-up of 11 +/- 9 years.

RESULTS

A diagnosis of dilated-hypokinetic HCM was made in 12 patients at first evaluation (11 without previous septal myectomy surgery; prevalence, 4.9%). Twelve of the 210 patients with classic HCM at first evaluation underwent dilated-hypokinetic evolution (incidence, 5.3/1,000 patient-years). Patients with prevalent/incident dilated-hypokinetic evolution were younger at first evaluation (32 +/- 14 years vs. 41 +/- 21 years, p = 0.04) and more often had a family history of HCM (61% vs. 26%, p = 0.002) or sudden death (43% vs. 19%, p = 0.01) with respect to patients who maintained classic HCM. Moreover, they showed greater interventricular septum (23 +/- 3 mm vs. 19 +/- 6 mm, p = 0.004) and posterior wall (15 +/- 3 mm vs. 13 +/- 4 mm, p = 0.006) thickness. Cardiovascular death-free survival was lower among patients with dilated-hypokinetic HCM (p < 0.04). Cox proportional hazards regression analysis identified left ventricular wall thickness (hazard ratio [HR] = 1.07; 95% confidence interval [CI], 1.01 to 1.14; p = 0.03) and end-diastolic diameter (HR = 1.08; 95% CI 1.04 to 1.11; p = 0.0001) as independent predictors of cardiovascular death.

CONCLUSIONS

Dilated-hypokinetic evolution is rare but not exceptional in HCM. Young age at diagnosis, family history of HCM, and greater wall thickness are incremental risk factors for dilated-hypokinetic HCM, which carries an ominous prognosis.

The influence of age on gender-specific differences in the left ventricular cavity size and contractility in patients with hypertrophic cardiomyopathy

BACKGROUND

The aim of the study was to assess gender-specific differences in left ventricular cavity size, contractility and left ventricular outflow tract obstruction in younger and older subgroups of patients with hypertrophic cardiomyopathy.

METHODS

We studied retrospectively 153 referred patients with hypertrophic cardiomyopathy (89 males and 64 females). The echocardiographically measured left ventricular end-systolic, end-diastolic dimensions, fractional shortening and occurrence of left ventricular outflow tract gradient were compared between sexes in subgroups of patients </=50 and >50 years of age.

RESULTS

In younger patients with hypertrophic cardiomyopathy, left ventricular end-diastolic and end-systolic dimensions were significantly smaller in females than males (41.9+/-5.8 vs. 44.7+/-5 mm P<0.01 23.4+/-5 vs. 25.2+/-5.4 mm P<0.05, respectively). Fractional shortening was comparable in both sexes (44.7+/-7.5 vs. 43.7+/-8.2% P>0.05). The left ventricular outflow tract gradient occurred in females as frequently as in males (13.3 vs. 17.6% P>0.05). In older patients with hypertrophic cardiomyopathy, left ventricular end-diastolic and end-systolic dimensions were also significantly smaller in females than males (42.5+/-6 vs. 46.3+/-3.2 mm P<0.02; 25.7+/-4.8 vs. 28.6+/-3.7 mm P<0.01, respectively). In contrast to the younger group, the fractional shortening was significantly higher in females than males (44.4+/-6.8 vs. 38.2+/-7.3% P<0.02). The left ventricular outflow tract gradient occurred in females more frequently than in males (63.2 vs. 20.8% P<0.02).

CONCLUSIONS

In patients with hypertrophic cardiomyopathy, the gender-based differences in the absolute value of left ventricular cavity size persisted with aging. In older females left ventricular contractility was higher and left ventricular outflow tract gradient occurred more frequently than in males. In younger patients with hypertophic cardiomyopathy these sex-based differences were absent. The gender-specific differences in the parameters of left ventricular systolic function became apparent with increasing age.

Do variable age-related secondary factors affect ventricular geometry in hypertrophic cardiomyopathy?

The relationship between cardiac shape and the age of patients with hypertrophic cardiomyopathy (HCM) has been established, and echocardiography has been accepted as the best method to quantitate ventricular cavity geometry. Recently, real-time three-dimensional volumetric data have demonstrated that children and young, middle-aged, and elderly patients with HCM have different morphologic and prognostic characteristics. This review discusses the importance of phenotypic expression and describes secondary factors that may affect ventricular cavity geometry during the progression of HCM.

Does the progression of myocardial fibrosis lead to atrial fibrillation in patients with hypertrophic cardiomyopathy?

The majority of left ventricular (LV) inflow volumes in hypertrophic cardiomyopathy (HCM) depend on atrial contraction because of impaired LV relaxation. If HCM is complicated by atrial fibrillation (AF), heart failure can develop because of the loss of atrial contraction. The purpose of this study was to determine the relationship between the development of AF and myocardial fibrosis or intramyocardial small artery (IMSA) stenosis in autopsied hearts with HCM. Studies were performed in five HCM hearts with AF (AF group) and five HCM hearts without AF (non-AF group). LV specimens were divided into the inner (IT), middle (MT), and outer (OT) thirds. We selected at random 120 fields and 20 IMSAs from each layer and assessed them quantitatively using an image analyzer. We determined the extent of fibrosis (%F) and the degree of stenosis of each IMSA (%L). The %F in the AF group was greater than in the non-AF group (P<.01). In the AF group, the %F of the IT was greater than in the MT and the OT (P<.01). In the non-AF group, the %F of the IT was greater than in the MT (P<.05), and the %F of the MT was greater than in the OT (P<.01). The %L was similar in the AF and non-AF groups. In both groups, the %L of the IT was lower than in the MT (P<.01), which was lower than that of the OT (P<.05). LV fibrosis is more severe in patients with HCM and AF than in those without AF. Therefore, myocardial fibrosis might impair LV relaxation, resulting in hemodynamic intolerance to AF.

[Value of Doppler-echocardiography in the prognosis and follow up of hypertrophic myocardiopathy]

INTRODUCTION AND OBJECTIVES

The aim of this study was to assess the value of Doppler-echocardiogram for the prognosis and follow up of a hospital-based series of adult patients with hypertrophic cardiomyopathy (HC).

METHODS

One-hundred nineteen consecutive patients with HC (52 +/- 12 years, 60 women) were studied over a follow up period of 9.7 +/- 6.7 years. Echocardiographic evolution was analyzed in 104 patients (67 with dynamic obstruction) who had, at least, two echocardiograms performed within an interval of 3.7 +/- 3 years (1 to 7 years).

RESULTS

Seven patients died during follow up and 31 patients developed severe complications (7 deaths, 15 syncopes, 4 class IV angina, 3 class IV dyspnea and 2 acute myocardial infarctions). The presence of mitral insufficiency (p = 0.001) and dynamic gradient > 50 mmHg (p = 0.02) were predictive of mortality and a left atrial index > 25 mm/m2 was predictive (p = 0.028) of severe complications. Fifteen percent of the patients without dynamic obstruction in the first Doppler-echo showed a gradient > 25 mmHg in the last echo. A greater number of patients with mitral insufficiency (80% vs 66%; p = 0.01) and an increase in its severity (p = 0.038) was observed during follow up.

CONCLUSIONS

Mitral insufficiency, a dynamic gradient > 50 mmHg and a left atrial index > 25 mm/m2 are variables of a bad prognosis in adult patients with HC. An evolution to obstructive HC was observed in 15% of non obstructive HC, and a tendency to increased severity of mitral insufficiency was observed during follow up.

Improvement in exercise capacity and exercise blood pressure response after transcoronary alcohol ablation therapy of septal hypertrophy in hypertrophic cardiomyopathy

Transcoronary alcohol ablation (TAA) therapy of septal hypertrophy was recently proposed as a therapeutic modality for obstructive hypertrophic cardiomyopathy (HC). However, questions remain about the effect of TAA on exercise performance. We performed a time-course analysis of exercise capacity and exercise hemodynamics in 20 patients with symptomatic obstructive HC after TAA. Symptom-limited bicycle exercise testing was performed before and 3 and 12 months after TAA, and cardiac catheterization at 3-month follow-up. The pressure gradient of the left ventricular outflow tract immediately decreased from 58 +/- 8 to 4 +/- 1 mm Hg at rest (p <0.01) and from 143 +/- 11 to 30 +/- 6 mm Hg after extrasystole (p <0.01), but partially recovered at 3-month follow-up (14 +/- 4 and 40 +/- 9 mm Hg, respectively). Left ventricular end-diastolic pressure was not changed after TAA. Peak oxygen consumption increased from 19 +/- 2 to 23 +/- 1 ml/kg/min (p < 0.01) and exercise duration from 573 +/- 47 to 742 +/- 46 seconds (p <0.01) at 3-month follow-up, but thereafter reached a plateau. Abnormal patterns of exercise blood pressure response were shown in 9 patients but normalized after TAA. Major complications occurred in 4 patients: no reflow to the left anterior descending coronary artery in 2 patients and ventricular tachycardia requiring cardioversion in 2 patients. During the follow-up period, all patients survived with symptomatic improvement in 17 patients. Thus, TAA is a promising therapeutic modality with improvement in exercise capacity and abnormal exercise blood pressure response in obstructive HC. However, potential serious complications should be considered in the application of TAA.

Morbidity outcome in patients with hypertrophic obstructive cardiomyopathy undergoing cardiac septal myectomy: early-extubation anesthesia versus high-dose opioid anesthesia technique

OBJECTIVE

Anesthetic management of patients with hypertrophic obstructive cardiomyopathy (HOCM) undergoing septal myectomy is challenging. The morbidity outcome of early-extubation anesthesia (EEA), or fast tracking, versus high-dose opioid (HDO) anesthesia was studied.

DESIGN

Retrospective study.

SETTING

University teaching hospital.

PARTICIPANTS

One hundred seventy-five cardiac septal myectomy patients (EEA, n = 53; HDO, n = 122).

INTERVENTIONS

EEA technique consisted of low-dose fentanyl, 10 to 15 microg/kg; propofol infusion; midazolam; and inhalation agent. HDO technique consisted of fentanyl, 50 to 100 microg/kg, and benzodiazepines, with or without an inhalation agent. Demographic data, preoperative symptoms, and data on anesthesia management and postoperative complications were recorded.

MEASUREMENTS AND MAIN RESULTS

There were no differences between the groups (EEA v HDO, respectively) regarding age, sex, preoperative symptoms (dyspnea, 89% v 79%; palpitations, 28% v 26%; angina, 47% v 61%; syncope, 47% v 41%), redo surgery, or combined surgery. Mean +/- standard deviation time to tracheal extubation was 7.2 +/- 5.3 hours in EEA versus 19.4 +/- 10.5 hours in HDO patients (p < 0.0001). Intensive care unit (ICU) stay was significantly shorter in EEA versus HDO patients (2.2 v 3.0 days; p < 0.005), with the trend toward earlier hospital discharge (9.7 v 11.3 days; p = 0.09). There was a high requirement for temporary pacing in both groups immediately postoperatively (EEA, 60% v HDO, 48%; p > 0.08). Permanent pacemaker insertion postoperatively was required in 7 of 53 patients (13%) in the EEA group and 11 of 122 patients (9%) in the HDO group (p > 0.25). Atrial arrhythmias occurred postoperatively in 25% of EEA patients versus 34% of HDO patients (p > 0.08).

CONCLUSION

EEA facilitates earlier tracheal extubation by 12 hours in patients with HOCM undergoing septal myectomy, significantly shortening ICU stay by 1 day without increasing perioperative cardiac morbidity or mortality.

Development of obstructive hypertrophic cardiomyopathy from nonobstructive hypertrophic cardiomyopathy

A rare case of obstructive hypertrophic cardiomyopathy (HC) with mitral regurgitation (MR) is reported, which developed over 7 years from nonobstructive HC in an elderly woman. Systolic anterior motion of the anterior mitral leaflet was the most likely cause of the outflow obstruction and mitral valve replacement combined with septal myectomy resulted in complete abolition of the outflow tract gradient and MR.

Marked expression of plasma brain natriuretic peptide is a special feature of hypertrophic obstructive cardiomyopathy

OBJECTIVES

We examined whether plasma brain natriuretic peptide levels are abnormally elevated in hypertrophic obstructive cardiomyopathy compared with other cardiac diseases.

BACKGROUND

We previously reported that plasma brain and atrial natriuretic peptide levels were elevated in hypertrophic cardiomyopathy.

METHODS

We compared plasma concentrations of brain and atrial natriuretic peptide and hemodynamic and echocardiographic data in 50 patients with hypertrophic obstructive cardiomyopathy (n = 15, mean [+/-SD] intraventricular pressure gradient 37 +/- 16 mm Hg), hypertrophic nonobstructive cardiomyopathy (n = 15), aortic stenosis (n = 10, mean pressure gradient 41 +/- 18 mm Hg) and hypertensive heart disease (n = 10, mean systolic/diastolic blood pressure 203 +/- 16/108 +/- 11 mm Hg, respectively) and 10 normal subjects.

RESULTS

Plasma brain natriuretic peptide levels were higher in the hypertrophic obstructive cardiomyopathy group (397.1 +/- 167.8 pg/ml*) than in the hypertrophic nonobstructive cardiomyopathy (60.0 +/- 48.1 pg/ml*), hypertensive heart disease (53.9 +/- 31.4 pg/ml*), aortic stenosis (75.4 +/- 54.3 pg/ml*) and normal groups (9.8 +/- 6.4 pg/ml [*p < 0.05 vs. normal group, p < 0.05 vs. hypertrophic obstructive cardiomyopathy group]). Although plasma atrial natriuretic peptide levels were higher in the hypertrophic obstructive cardiomyopathy group than the other patient groups, the brain/atrial natriuretic peptide ratio in the hypertrophic obstructive cardiomyopathy group was higher (4.5 +/- 2.3) than those in the other three patient groups (1.1 to 1.4) and the normal group (0.7 +/- 0.5). Left ventricular end-diastolic pressure and left ventricular end-diastolic volume index were similar among the four patient groups. The interventricular septal thickness and the ratio of interventricular septal thickness to left ventricular posterior wall thickness were similar between the hypertrophic obstructive and nonobstructive cardiomyopathy groups.

CONCLUSIONS

Abnormal elevations of plasma brain natriuretic peptide levels are difficult to explain on the basis of hemodynamic and echocardiographic data and are a special feature of hypertrophic obstructive cardiomyopathy.

Hypertrophic cardiomyopathy. Clinical spectrum and treatment

HCM is a heterogeneous disease genotypically, phenotypically, pathophysiologically, clinically, and therapeutically. In decisions on the management of these patients, it is important to recognize this heterogeneity and to direct therapy at the predominant abnormalities.

Coexistence of sudden cardiac death and end-stage heart failure in familial hypertrophic cardiomyopathy

OBJECTIVES

The purpose of this study was to determine the occurrence of sudden cardiac death or end-stage heart failure, two phases of the natural history of hypertrophic cardiomyopathy, in closely related relatives.

BACKGROUND

Hypertrophic cardiomyopathy is a genetically transmitted cardiac disease with a particularly diverse clinical and morphologic spectrum. Premature death usually occurs either suddenly or as a result of progressive congestive heart failure.

METHODS

We describe seven families with genetically transmitted hypertrophic cardiomyopathy that were studied with echocardiography or necropsy, or both, and were selected because they were known to include relatives who had incurred either premature sudden cardiac death or the end-stage phase of the disease.

RESULTS

The seven families comprised 128 relatives; 26 died suddenly, and 9 developed end-stage heart failure (including 2 with heart transplantation) associated with left ventricular cavity enlargement, wall thinning or decreased contractility, alone or in combination, as well as loss of outflow obstruction. Patients who died suddenly did so at younger ages (23 +/- 10 years) than did patients who died or required heart transplantation in the end-stage phase of hypertrophic cardiomyopathy (42 +/- 8 years, p < 0.001).

CONCLUSIONS

This study demonstrates that family members with hypertrophic cardiomyopathy, despite a common genetic substrate, may exhibit markedly diverse and distinct expressions of the natural history of their disease, which occur at widely separated periods of life.

Rapid progression of septal hypertrophy in an adult with hypertrophic cardiomyopathy and excimer laser-treated coronary artery disease

We present the case of a 55-year-old man with rapid progression from asymmetrical septal hypertrophy to hypertrophic obstructive cardiomyopathy over a 1-year period leading to persistent anginal symptoms despite adequate treatment of his concomitant coronary artery disease. The potential mutagenic side effects of XeCl excimer laser-radiation that was used to remove the arteriosclerotic plaque from the left anterior descending coronary artery may have contributed to the sudden increase in septal thickness.

Clinical significance of coronary artery disease in hypertrophic cardiomyopathy

The role of coronary artery disease (CAD) in hypertrophic cardiomyopathy (HC) has not been thoroughly clarified. To assess the clinical and prognostic significance of these 2 coexistent diseases, 96 patients with HC (62 men, mean age 45 years) who underwent coronary arteriography and 2-dimensional echocardiography were studied. Significant stenosis (greater than 70%) of 1 or more coronary arteries was detected in 11 patients, all aged greater than 45 years. This group, compared with the other group without significant CAD (n = 85), was characterized by an older age (59 +/- 7 vs 42 +/- 15 years; p less than 0.05), a greater prevalence of previous myocardial infarction (24 vs 0%; p less than 0.001), complex ventricular arrhythmias (100 vs 50%; p less than 0.05), non-obstructive forms (82 vs 46%; p less than 0.05), dilated (45 vs 7%; p less than 0.02) and hypocontractile left ventricle (36 vs 6%; p less than 0.01) and higher mortality (36 vs 8%; p less than 0.05) during a mean follow-up of 3.6 years. It is concluded that CAD associated with HC is a complex clinical syndrome, difficult to diagnose clinically, that can reliably be recognized by coronary angiography. CAD seems to play an important role in modifying the pathophysiology, the natural history and the prognosis of HC.

Electrocardiographic findings in patients with hypertrophic cardiomyopathy. Relation to presenting features and prognosis

The relation of ECG findings to presenting features and prognosis was evaluated in 125 consecutive patients with hypertrophic cardiomyopathy (HC). Seventy-nine men and 46 women (mean age, 34 +/- 7 years) were studied since 1970. Most ECG features were similar in patients with and without a left ventricular outflow tract gradient. Those with obstruction had a higher prevalence of left ventricular hypertrophy according to ECG voltage criteria (54% vs. 28%, p less than 0.01), whereas higher grade ventricular arrhythmias were more common in patients without an outflow gradient (20% vs. 7%, p less than 0.05). The prevalence of ECG abnormalities was also similar in younger (less than or equal to 14 years) and older patients (greater than 14 years), and only repolarization abnormalities were more frequently detected in the older age group (56% vs. 32%, p less than 0.025). Stratification of patients according to the clinical state revealed that those who had moderate to severe functional limitation had a higher prevalence of atrial fibrillation than asymptomatic or mildly symptomatic patients (24% vs. 1%, p less than 0.001). There were no significant differences in most hemodynamic variables among patients dichotomized according to any specific ECG abnormality. Only patients with atrial fibrillation had significantly higher right ventricular end-diastolic pressure (10 +/- 7 vs. 6 +/- 4 mmHg, p less than 0.01), lower systolic index (22 +/- 8 vs. 37 +/- 15 ml/m2; beat, p less than 0.02) and lower ejection fraction (53 +/- 8 vs. 64 +/- 10%, p less than 0.001) than those in sinus rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)

The significance of increased left ventricular outflow tract velocities in the elderly measured by continuous wave Doppler

Forty-four elderly patients (mean age 80 +/- 7 years) with elevated left ventricular outflow tract velocities and corresponding outflow tract gradients documented by continuous wave Doppler are reported (mean peak gradient 50 +/- 28). They had severe left ventricular hypertrophy, small left ventricular end-diastolic dimensions, and supernormal ejection fractions. Thirty-nine percent had a history of hypertension. They were predominantly female, had uniform concentric left ventricular hypertrophy, and had a high incidence of congestive heart failure. Diastolic function was found to be reduced in the elderly group compared to young patients with hypertrophic cardiomyopathy and to age- and sex-matched normal controls. It is concluded that most elderly patients with increased left ventricular outflow tract velocities are etiologically distinct from young patients with hypertrophic cardiomyopathy.

Development of severe left ventricular outflow tract obstruction over the course of 14 years: an unusual natural history of hypertrophic obstructive cardiomyopathy

A patient with hypertrophic obstructive cardiomyopathy who when first seen had a normal physial examination, chest x-ray, and electrocardiogram, and no provokable gradient with isoproterenol at cardiac catheterization, was re-evaluated after 14 years. At the time of re-evaluation, she was found to have a typical systolic ejection murmur, cardiomegaly, left ventricular hypertrophy, a pseudoinfarction pattern on electrocardiography, and a significant subaortic gradient both by catheterization and by doppler. This case demonstrates that hypertrophic obstructive cardiomyopathy can be a progressive disease and that patients with this condition warrant careful follow-up. Echocardiography with doppler may provide an excellent noninvasive method of following these patients.

Hypertrophic cardiomyopathy. The importance of the site and the extent of hypertrophy. A review

Hypertrophic cardiomyopathy is a diverse clinical and pathophysiologic entity that involves principally the left ventricle and is caused by asymmetric or concentric hypertrophy of unknown cause. If asymmetric, the hypertrophy is usually greatest in the ventricular septum, but variations occur in which the hypertrophy may be maximal at the apex, at the midventricular level, or, rarely, in the free wall of the left ventricle. Right ventricular involvement is usually less evident. The principal abnormality in systole is the obstruction to left ventricular outflow caused by upper septal hypertrophy narrowing the outflow tract and setting the stage for Venturi forces to cause systolic anterior motion of the anterior or posterior mitral leaflets. The time of onset and duration of mitral leaflet-septal contact determine the magnitude of the pressure gradient. Mitral regurgitation invariably accompanies the obstruction to outflow. Ventriculomyotomy-myectomy surgery, by thinning the septum and widening the outflow tract, abolishes the abnormal mitral leaflet motion and, consequently, the obstruction to outflow and the mitral regurgitation. This form of surgery more dramatically relieves the systolic abnormalities and the accompanying symptoms than any form of medical therapy available today. The extent of hypertrophy is believed to be the principal determinant of the impaired left ventricular relaxation and increased chambers stiffness (decreased compliance) that characterize diastole in hypertrophic cardiomyopathy. Relaxation is impaired by the contraction load (the obstruction), by a decrease in the principal relaxation loads, by a pathologic degree of nonuniformity of contraction and relaxation, and in all likelihood, by impaired inactivation of the biochemical processes responsible for contraction (? due to primary or ischemia-induced calcium overload). Calcium channel-blocking agents may dramatically improve left ventricular relaxation by speeding up the inactivation process, by decreasing the degree of nonuniformity, or by altering the contraction and relaxation loads in a favorable manner. Atrial and ventricular arrhythmias are responsible for a significant proportion of the morbidity and mortality, and their occurrence also appears to depend on the extent of hypertrophy. Thus, the major manifestations of hypertrophic cardiomyopathy in systole and diastole as well as the disturbances of rhythm appear to be related to the site and/or extent of the hypertrophic process.(ABSTRACT TRUNCATED AT 400 WORDS)

Relation of left ventricular function and prognosis in hypertrophic cardiomyopathy: an angiographic study

Left ventricular cineangiograms performed at the time of diagnosis in 88 patients with hypertrophic cardiomyopathy were digitized to evaluate the relation of left ventricular function and prognosis in hypertrophic cardiomyopathy. Eleven patients died suddenly after a mean follow-up period of 7.5 +/- 7 years, 10 patients died of congestive heart failure or after cardiac surgery and 67 were alive after a mean follow-up period of 8.6 +/- 4 years. Measurements of left ventricular volume, ejection fraction, peak rate of ejection and filling and time to peak rate of ejection and filling were derived from curves of ventricular volume and its rate of change during the cardiac cycle. Patients who died suddenly had a lower peak rate of ventricular ejection (stroke volume-normalized peak ejection rate 5.41 +/- 0.69 versus 6.24 +/- 1.33 s-1; p = 0.006) and lower peak rate of ventricular filling (end-diastolic volume-normalized peak filling rate 4.02 +/- 0.94 versus 4.88 +/- 1.53 s-1; p = 0.02) and stroke volume-normalized peak filling rate (4.75 +/- 1.08 versus 5.82 +/- 1.70 s-1; p = 0.01) compared with survivors. Stepwise regression analysis revealed that sudden death was best predicted by the combination of increased end-diastolic volume, small end-systolic volume and low peak filling rate (predictive accuracy 32%, false negative 18% and false positive 28%). The addition of clinical features and hemodynamic measurements to the analysis improved predictive accuracy to 43% (false negative 18% and false positive 18%). Ambulatory electrocardiographic monitoring performed in 57 of the 88 patients 1 month to 17 years (median 8 years) after diagnosis revealed ventricular tachycardia in 14 (25%). Of these, 10 who survived had hyperkinetic systolic function at diagnosis, whereas the 4 who died suddenly had impaired systolic function (end-diastolic volume-normalized peak ejection rate 5.93 +/- 1.2 versus 4.01 +/- 1.2 s-1, respectively; p = 0.04). In hypertrophic cardiomyopathy, ventricular tachycardia is a sensitive but nonspecific marker of adults who are at risk of sudden death. Impaired systolic function may be an important determinant of which patients with ventricular tachycardia die suddenly. This study shows that indexes of ventricular function contribute to the identification of patients at particular risk of sudden death. However, the predictive power of the clinical features and hemodynamic and angiographic measurements that could be assessed was poor.(ABSTRACT TRUNCATED AT 400 WORDS)