Jun Takata

Mechanisms of exercise limitation in hypertrophic cardiomyopathy

To assess the relation of exercise capacity to indexes of systolic and diastolic function in hypertrophic cardiomyopathy, 81 patients underwent two-dimensional echocardiography, technetium-99m equilibrium radionuclide angiography acquired in list mode and maximal, symptom-limited, treadmill exercise testing with measurement of maximal oxygen consumption (VO2 max). VO2 max for the group was 13.9 to 49.3 (mean 25.4) ml/min per kg. Thirty-six patients (44%) achieved less than or equal to 70% of age-predicted VO2 max. Patients with such a degree of limitation were more likely to be in New York Heart Association functional class II or III (23 of 36 vs. 14 of 45; p = 0.005); there was no such relation between VO2 and the incidence and magnitude of rest left ventricular outflow tract pressure gradient greater than 30 mm Hg (11 of 36 vs. 11 of 45; p = NS and 58 +/- 24 vs. 65 +/- 19 mm Hg; p = NS). In the 22 patients with a left ventricular outflow tract gradient, the ratios of peak ejection to peak filling rate and of atrial contribution to left atrial dimension were related to percent of the age-predicted VO2 max (r = 0.49, p = 0.02 and r = 0.54, p less than 0.02). These ratios reflect impaired left ventricular systolic performance and atrial systolic failure, respectively. Stepwise discriminant analysis revealed these two ratios to be the two strongest predictors (p = 0.0001) of patients with a left ventricular outflow tract gradient whose VO2 max was less than or equal to 70% of the age-predicted value (sensitivity 90%, specificity 100%).(ABSTRACT TRUNCATED AT 250 WORDS)

High Morning Home Blood Pressure Is Associated with a Loss of Functional Independence in the Community-Dwelling Elderly Aged 75 Years or Older

To elucidate the relationship between home systolic blood pressure (SBP) and functional impairment in the elderly 75 years or older, 461 community-dwelling subjects (192 men, 269 women, mean age: 80 years) were studied. Home blood pressure was measured twice in the morning and twice in the evening for 5 consecutive days with an automatic cuff-oscillometric device. Total/high-density lipoprotein cholesterol and several functional assessments were evaluated. A subject was determined to exhibit a loss of independence according to the activities of daily living (ADL) score in a study conducted in 2001. Based on the mean home SBPs (mSBP) and morning–evening SBP differences (dSBP), the subjects were classified into 4 groups as follows: hypertensive/morning-dominant (HM; mSBP≥135 mmHg, dSBP≥15 mmHg), hypertensive/sustained (HS; mSBP≥135 mmHg, dSBP<15 mmHg), normotensive/morning-dominant (NM; mSBP<135 mmHg, dSBP≥15 mmHg), and normotensive/controlled (NC; mSBP<135 mmHg, dSBP<15 mmHg). There were no differences in sex, cholesterol levels, history of stroke, other cardiovascular diseases (CVDs), and cognitive function, but there were significant differences in age, antihypertensive medications, the neurobehavioral test scores, and ADL scores. There were no significant differences in terms of mortality and CVD events. In the survivors, HM and HS were independent risk factors for a loss of independence, after adjustments were made for onset of stroke, age, antihypertensive therapy, history of CVD, as well as neurobehavioral test scores and ADL scores (odds ratio [OR]: 12.2 and 3.78, respectively). After the same adjustments as those mentioned above were made, HM and HS were found to be negative determinants of survival and maintenance of independence (OR: 0.082, 0.270, respectively). In conclusion, high home SBP (≥135 mmHg) and high dSBP (≥15 mmHg) were found to be important in determining the levels of disability for the very elderly.

Effect of left ventricular reverse remodeling on long-term prognosis after therapy with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers and β blockers in patients with idiopathic dilated cardiomyopathy.

It remains unknown whether left ventricular (LV) reverse remodeling (LVRR) after therapy with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers and β blockers is correlated with prognosis in patients with idiopathic dilated cardiomyopathy. Forty-two patients with idiopathic dilated cardiomyopathy treated with the therapy were studied. Complete left ventricular reverse remodeling was defined as LV end-diastolic dimension ≤ 55 mm and fractional shortening ≥ 25% at the last echocardiographic assessment. The incidence of complete LVRR was significantly higher in patients who survived than in those who died or underwent heart transplantation. Patients were divided into 3 groups: death or transplantation, alive with complete LVRR, and alive without complete LVRR. Although patients who died or underwent transplantation did not show any LV improvements, those with complete LVRR showed significant improvements at 1 to 6 months after starting the therapy. Patients without complete LVRR also showed small but significant improvements at 1 to 6 months. The decrease in LV end-systolic dimension from the initial value to that at 1 to 6 months was an independent determinant of future cardiac death or transplantation. In conclusion, complete LVRR is related to favorable prognosis in patients with idiopathic dilated cardiomyopathy. The extent of left ventricular reverse remodeling at 1 to 6 months after starting the therapy is predictive of long-term prognosis.

Association between brachial–ankle pulse wave velocity and 3-year mortality in community-dwelling older adults

With aging, arterial stiffness increases and results in cardiovascular diseases. Recently, high brachial–ankle pulse wave velocity (baPWV), measured using a new noninvasive device to estimate arterial stiffness, was reported to be associated with the prevalence of cardiovascular diseases. The purpose of this study was to clarify the association between baPWV with 3-year mortality in community-dwelling older adults and to determine the cutoff value of baPWV in terms of mortality. A total of 530 subjects aged 65 years or older (men/women, 207:323; mean age, 76 years) participated. They were dichotomized by the median value of baPWV. Within 3 years, 30 deaths occurred, including 11 cardiovascular deaths. The high-baPWV group had a higher incidence of total deaths (high-baPWV group vs. low-baPWV group, 8.3 vs. 3.0%, respectively) and cardiovascular deaths (high-baPWV group vs. low-baPWV group, 3.8 vs. 0.4%, respectively). A high-baPWV level was associated with an increased risk of 3-year total mortality after adjustment for age, sex and systolic blood pressure (hazard ratio for high baPWV vs. low baPWV=2.98, 95% CI=1.25–7.07) and with an increased risk of 3-year cardiovascular mortality (hazard ratio for high baPWV vs. low baPWV=10.01, 95% CI=1.21–82.49). A receiver-operating characteristic curve showed that the optimal cutoff value of baPWV for total mortality was 19.63 m s−1, and for cardiovascular mortality it was 19.63 m s−1. This study provides a preliminary finding that assessment of arterial stiffness by baPWV might be a useful method to predict mortality risk in community-dwelling older adults. Large longitudinal studies for extended periods of time are necessary to confirm the association.

Left Ventricular Reverse Remodeling in Long-Term (>12 Years) Survivors With Idiopathic Dilated Cardiomyopathy

Little is known about left ventricular (LV) reverse remodeling (LVRR) in long-term survivors with idiopathic dilated cardiomyopathy. We studied 59 patients with idiopathic dilated cardiomyopathy who had a potential clinical and echocardiographic follow-up period of >12 years. LVRR was defined as LV end-diastolic dimension ≤ 55 mm and fractional shortening ≥ 25% on the last echocardiogram. Of the 59 patients, 38 died (heart failure in 20, sudden death in 11, and other causes in 7), 2 underwent transplantation, and 19 survived. In the survivors, the LV size had significantly decreased and LV fractional shortening had significantly increased on the last echocardiogram. LVRR occurred in 37% of the survivors. The remaining 63% of the survivors still had LV dysfunction, but the LV end-systolic dimension had decreased significantly. In patients who died or underwent transplantation, the LV size significantly increased. No patient who died or underwent transplantation had LVRR. In conclusion, >60% of the long-term (>12 years) survivors with idiopathic dilated cardiomyopathy still had LV systolic dysfunction, but the LV end-systolic dimension had decreased significantly. In contrast, patients who died or underwent transplantation had significant LV enlargement. These results suggest that LVRR, even if it is not marked, is associated with a favorable prognosis.

Delayed recovery of postexercise blood pressure in patients with chronic heart failure

Thirty-four patients with idiopathic dilated and ischemic cardiomyopathy underwent a symptom-limited cardiopulmonary exercise testing to evaluate the significance of postexercise blood pressure (BP) response. The postexercise BP response was useful in assessing the impaired exercise capacity and increased sympathetic activity in patients with heart failure.

Improvement in prognosis of dilated cardiomyopathy in the elderly over the past 20 years.

BACKGROUND AND PURPOSE Although dilated cardiomyopathy (DCM) had a poor prognosis in the past, recent studies have shown better survival. However, little is known about the improvement of prognosis in the elderly. This study sought to clarify the changes in prognosis in elderly patients with DCM over the past 20 years. METHODS AND SUBJECTS We studied 54 consecutive patients with DCM (38 men and 16 women, aged 65-83 years) who were diagnosed at over 65 years of age. The patients were divided into two groups (group A: 12 patients diagnosed before 1990; group B: 42 patients diagnosed after 1990) because after 1990, based on growing evidence from large-scale, randomized clinical studies, we intentionally increased the use of angiotensin-converting enzyme inhibitors (ACEI) and then beta-blockers at our hospital. RESULTS There were no significant differences in age, gender, NYHA functional class, and the prevalence of atrial fibrillation and ventricular tachycardia between the two groups. Left ventricular (LV) size assessed by echocardiography was larger (LV end-diastolic diameter, 67+/-5.9 versus 62+/-6.6 mm; p=0.039) and LV ejection fraction measured by left ventriculography was lower (ejection fraction, 24+/-9 versus 35+/-10%; p=0.004) in group A. ACEI/angiotensin II type 1 receptor blockers (ARB) (0% versus 88%) or beta-blockers (0% versus 52%) were more frequently used in group B. Antiarrhythmics (class Ia or Ib) (75% versus 14%) were less often used in group B. The 5- and 10-year event-free survival rates for cardiac death were 75.4% and 22.0% in group A versus 81.2% and 71.3% in group B (log-rank test, p=0.014). CONCLUSIONS The prognosis of DCM patients in the elderly has significantly improved over the past 20 years. The advances in the pharmacologic treatment and earlier diagnosis may have contributed to the better survival.

Clinical and Electrocardiographic Profiles Producing Exercise-Induced U-Wave Inversion in Patients With Severe Narrowing of the Left Anterior Descending Coronary Artery

To elucidate which clinical features produce U-wave inversion, 339 patients with severe narrowing of the left anterior descending artery were evaluated. In patients with anterior myocardial infarction, extensive coronary artery disease and protected left anterior descending arterial territory are essential in the development of U-wave inversion, whereas electrocardiographic changes at rest in addition to anterior lead ST depression, rather than coronary anatomy, are important in those without anterior myocardial infarction.

Clinical Features of the Dilated Phase of Hypertrophic Cardiomyopathy in Comparison With Those of Dilated Cardiomyopathy

Although the dilated phase of hypertrophic cardiomyopathy (D‐HCM) characterized by left ventricular (LV) systolic dysfunction and cavity dilatation has been reported to be a poor prognosis, this is now in contrast to the improved prognosis of dilated cardiomyopathy (DCM) in the era of advancements in heart failure management. There has been no investigation of the clinical features of D‐HCM compared with those of DCM from the point of management of systolic dysfunction.

Effect of Diltiazem on Sympathetic Hyperactivity in Patients With Vasospastic Angina as Assessed by Spectral Analysis of Arterial Pressure and Heart Rate Variability

The autonomic nervous system importantly regulates coronary arterial tone and vascular resistance. To evaluate a role of autonomic nervous activity and the effects of calcium antagonist in patients with vasospastic angina (VSA), 13 VSA patients with patent coronary arteries (58+/-8 years) and 8 normal subjects (58+/-12 years) were studied. Arterial pressure and electrocardiogram were continuously recorded with the patient in a supine position under controlled respiration (0.2 Hz). Low-frequency (LF) and high-frequency (HF) components of the beat-to-beat variabilities of systolic arterial pressure and RR interval were then estimated by autoregressive power spectral analysis. The LF power (normalized unit) of both systolic arterial pressure (0.53+/-0.17 vs 0.30+/-0.17, p < 0.01) and RR variabilities (0.51+/-0.20 vs 0.31+/-0.16, p < 0.05) in patients with VSA were greater than that in normal subjects. There was no significant difference in the HF power. Seven patients with VSA who were treated with diltiazem (60 to 200 mg/day) had normalized LF power (normalized unit) of both systolic arterial pressure (0.62+/-0.12 vs 0.33+/-0.16, p < 0.01) and RR variabilities (0.55+/-0.23 vs 0.36+/-0.14, p < 0.05), together with clinical improvement. An increased sympathetic vasomotor tone and cardiac sympathetic predominance may play an important role in patients with VSA. Diltiazem improves these sympathetic hyperactivities.