Afonso Yoshikiro Matsumoto

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.

Prognosis in Dilated Myocardial Disease: Influence of Diastolic Dysfunction and Anatomical Changes

A prospective study has been conducted, in patients with dilated myocardial disease, in order to examine the relation between echocardiographic variables and mortality rate. Patients were divided into two major groups: (1) group A—designed to evaluate the influence of the ventricular filling pattern in the mortality rate. It included 95 patients, followed‐up for a period ranging from 1–23 months (mean = 12.6 months), divided into three subgroups: AF (atrial filling predominant pattern, n = 22); N (normal or “normalized” filling pattern, n = 40), and RF (rapid filling predominant pattern, n = 33); and (2) group B—designed to correlate echocardiographic variables to the 1‐year mortality rate. It included 52 patients divided into two subgroups: survivors (n = 40) and nonsurvivors (n = 12). In group A, a progressive decrease in survival rate was noted on comparing subgroups N to AF to RF. At the 14 months follow‐up a survival rate of 89% was noted in N, 75% in AF, and 50% in RF. Univariate analysis in group B showed high 1‐year mortality rate associated with mitral flow deceleration time ≤ 140 msec (50%, P = 0.003), left ventricular diastolic diameter/thickness ratio ≥ 3.4 (35.3%, P = 0.002), and left atrial index ≥ 25 mm/m2 (40.7%, P = 0.001). The highest mortality rate (61.5%, P = 0.0004) was observed in patients with increased left atrial index and decreased deceleration time. Thus, diastolic dysfunction and anatomical changes, as evaluated by echocardiography, are confident parameters to estimate the prognosis in dilated myocardial disease.

Usefulness of a new proposed tissue Doppler imaging global function index in hypertrophic cardiomyopathy.

Background: A global function index (GFI) derived from tissue Doppler imaging (TDI) has been proposed to improve the diagnosis of hypertrophic cardiomyopathy (HCM). We aimed to evaluate the usefulness of this index in a large selected HCM population. Methods: GFI =[E/Ea]/Sa, was calculated at mitral annulus lateral and septal borders in 164 HCM patients and in 40 healthy volunteers. Group comparisons and correlations between GFI and other variables were performed. Results: Of the 164 patients, 69 (42%) had a peak gradient >30 mmHg in the left ventricle outflow tract (LVOT). GFI (lateral or septal) was not normally distributed. There were differences among controls, obstructive HCM, and nonobstructive HCM (P < 0.0001), but significant overlap of GFI values were observed between groups. GFI was correlated to septal thickness (r = 0.44; P < 0.0001), left atrial diameter (r = 0.52; P < 0.0001), and LVOT gradient (r = 0.58; P < 0.0001). Conclusion: In a selected HCM population, GFI was limited by its asymmetrical distribution and significant overlap of values between groups. Further studies are necessary to verify the reliability of GFI in the clinical practice and its position among other tissue Doppler indices.

Association of angiotensin-converting enzyme activity and polymorphism with echocardiographic measures in familial and nonfamilial hypertrophic cardiomyopathy

Angiotensin-converting enzyme (ACE) activity and polymorphism contribute significantly to the prognosis of patients with cardiomyopathy. The aim of this study was to determine the activity and type of ACE polymorphism in patients with familial and nonfamilial hypertrophic cardiomyopathy (HCM) and to correlate these with echocardiographic measurements (echo-Doppler). We studied 136 patients (76 males) with HCM (69 familial and 67 nonfamilial cases). Mean age was 41 +/- 17 years. DNA was extracted from blood samples for the polymerase chain reaction and the determination of plasma ACE levels. Left ventricular mass, interventricular septum, and wall thickness were measured. Mean left ventricular mass index, interventricular septum and wall thickness in familial and nonfamilial forms were 154 +/- 63 and 174 +/- 57 g/m(2) (P = 0.008), 19 +/- 5 and 21 +/- 5 mm (P = 0.02), and 10 +/- 2 and 12 +/- 3 mm (P = 0.0001), respectively. ACE genotype frequencies were DD = 35%, ID = 52%, and II = 13%. A positive association was observed between serum ACE activity and left ventricular mass index (P = 0.04). Logistic regression showed that ACE activity was twice as high in patients with familial HCM and left ventricular mass index >or=190 g/m(2) compared with the nonfamilial form (P = 0.02). No other correlation was observed between ACE polymorphisms and the degree of myocardial hypertrophy. In conclusion, ACE activity, but not ACE polymorphisms, was associated with the degree of myocardial hypertrophy in the patients with HCM.

Endothelial and Non-Endothelial Coronary Blood Flow Reserve and Left Ventricular Dysfunction in Systemic Hypertension

OBJECTIVES: We evaluated the impairment of endothelium-dependent and endothelium-independent coronary blood flow reserve after administration of intracoronary acetylcholine and adenosine, and its association with hypertensive cardiac disease. INTRODUCTION: Coronary blood flow reserve reduction has been proposed as a mechanism for the progression of compensated left ventricular hypertrophy to ventricular dysfunction. METHODS: Eighteen hypertensive patients with normal epicardial coronary arteries on angiography were divided into two groups according to left ventricular fractional shortening (FS). Group 1 (FS ≥0.25): n=8, FS=0.29 ± 0.03; Group 2 (FS <0.25): n=10, FS= 0.17 ± 0.03. RESULTS: Baseline coronary blood flow was similar in both groups (Group 1: 80.15 ± 26.41 mL/min, Group 2: 100.09 ± 21.51 mL/min, p=NS). In response to adenosine, coronary blood flow increased to 265.1 ± 100.2 mL/min in Group 1 and to 300.8 ± 113.6 mL/min (p <0.05) in Group 2. Endothelium-independent coronary blood flow reserve was similar in both groups (Group 1: 3.31 ± 0.68 and Group 2: 2.97 ± 0.80, p=NS). In response to acetylcholine, coronary blood flow increased to 156.08 ± 36.79 mL/min in Group 1 and to 177.8 ± 83.6 mL/min in Group 2 (p <0.05). Endothelium-dependent coronary blood flow reserve was similar in the two groups (Group 1: 2.08 ± 0.74 and group Group 2: 1.76 ± 0.61, p=NS). Peak acetylcholine/peak adenosine coronary blood flow response (Group 1: 0.65 ± 0.27 and Group 2: 0.60 ± 0.17) and minimal coronary vascular resistance (Group 1: 0.48 ± 0.21 mmHg/mL/min and Group 2: 0.34 ± 0.12 mmHg/mL/min) were similar in both groups (p= NS). Casual diastolic blood pressure and end-systolic left ventricular stress were independently associated with FS. CONCLUSIONS: In our hypertensive patients, endothelium-dependent and endothelium-independent coronary blood flow reserve vasodilator administrations had similar effects in patients with either normal or decreased left ventricular systolic function.

Left ventricular pseudoaneurysm due to penetrating injury of the chest: an echocardiographic diagnosis.

5. Ramirez CA, Naraqi S, McCulley DJ. Group A P-hemolytic streptococcus endocarditis. AM HEART J 1984;108:1383-6. Shaffer EM, Snider AR, Beckman RH, Behrendt DM, Peschiera AW. Sinus of Valsalva aneurysm complicating bacterial endocarditis in an infant: diagnosis with two-dimensional and Doppler echocardiography. J Am Co11 Cardiol 1987; 9:588-91. Vered Z, Roth S, Benjamin P, Motro M, Neufeld HN. Ruptured sinus of Valsalva: demonstration by contrast echocardiography during cardiac catheterization. AM HEART J 1985;109:365-6. Valdes-Cruz LM, Pierone DR, Roland JM, Varghese PJ. Echocardiographic detection of intracardiac right-to-left shunts following peripheral vein injections. Circulation 1976;54:558-62. Gillam LD, Kaul S, Fallon JT, et al. Functional and pathologic effects of multiple echocardiographic contrast injections on the myocardium, brain and kidney. J Am Co11 Cardiol 1985;6:687-94.

Left ventricular function after a single large dose of verapamil.

The effects of a single large dose of verapamil on left ventricular (LV) function were evaluated noninvasively in 18 chronically hypertensive patients. Each patient was given a single oral dose of verapamil, 240 mg, before and after which arterial blood pressure was measured and an echocardiogram and a phonomechanocardiogram were obtained. Reactional symmetrical myocardial hypertrophy was seen in all patients on the first echocardiogram. Results showed that heart rate was not significantly altered, but there were significant decreases (p less than 0.01) in systolic blood pressure (183.89 to 127.56 mm Hg) and diastolic blood pressure (101.11 to 77.67 mm Hg). The following parameters were also significantly decreased (p less than 0.01): LV ejection time (294.56 to 274.22 ms), LV diastolic diameter (45.78 to 43.99 mm), percentage change in LV diameter (33 to 27.83%), mean velocity of circumferential fiber shortening (1.12 to 1.02 cir/s), posterior wall contraction velocity (40.83 to 36.28 mm/s), LV end-diastolic volume (97.78 to 86.89 cm3), ejection fraction (0.70 to 0.62), stroke volume (70 to 55 cm3) and cardiac output (4.7 to 4 liters/m). Three parameters were significantly increased (p less than 0.01): preejection period (104.06 to 112.06 ms), preejection period: LV ejection time ratio (0.35 to 0.41) and end-systolic volume (29.28 to 32.33 cm3). It is concluded that a single oral dose of verapamil, 240 mg, is highly efficient in lowering arterial blood pressure in chronically hypertensive patients and in reducing the peripheral resistance and LV performance indexes.

Exercise-induced quantitative microvolt T-wave alternans in hypertrophic cardiomyopathy.

BACKGROUND/PURPOSE Patients with hypertrophic cardiomyopathy (HCM) have elevated risk for sudden cardiac death (SCD). Our study aimed to quantitatively characterize microvolt T-wave alternans (TWA), a potential arrhythmia risk stratification tool, in this HCM patient population. METHODS TWA was analyzed with the quantitative modified moving average (MMA) in 132 HCM patients undergoing treadmill exercise testing, grouped according to Maron score risk factors as high-risk (H-Risk, n=67,), or low-risk (L-Risk, n=65, without these risk factors). RESULTS TWA levels were much higher for the H-Risk than for the L-Risk group (101.40±75.61 vs. 54.35±46.26μV; p<0.0001). A 53μV cut point, set by receiver operator characteristic (ROC), identified H-Risk patients (82% sensitivity, 69% specificity). CONCLUSIONS High TWA levels were found for hypertrophic cardiomyopathy patients. Abnormal TWA associated with major risk factors for SCD: non-sustained ventricular tachycardia on Holter (p=0.001), family history of SCD (p=0.006), septal thickness ≥30mm (p<0.001); and inadequate blood pressure response to effort (p=0.04).

Left Atrial Function in Patients with Chronic ChagasicCardiomyopathy

Background Chagas disease is a cause of dilated cardiomyopathy, and information about left atrial (LA) function in this disease still lacks. Objective To assess the different LA functions (reservoir, conduit and pump functions) and their correlation with the echocardiographic parameters of left ventricular (LV) systolic and diastolic functions. Methods 10 control subjects (CG), and patients with Chagas disease as follows: 26 with the indeterminate form (GI); 30 with ECG alterations (GII); and 19 with LV dysfunction (GIII). All patients underwent M-mode and two-dimensional echocardiography, pulsed-wave Doppler and tissue Doppler imaging. Results Reservoir function (Total Emptying Fraction: TEF): (p <0.0001), lower in GIII as compared to CG (p = 0.003), GI (p <0.001) and GII (p <0.001). Conduit function (Passive Emptying Fraction: PEF): (p = 0.004), lower in GIII (GIII and CG, p = 0.06; GI and GII, p = 0.06; and GII and GIII, p = 0.07). Pump function (Active Emptying Fraction: AEF): (p = 0.0001), lower in GIII as compared to CG (p = 0.05), GI (p<0.0001) and GII (p = 0.002). There was a negative correlation of E/e’average with the reservoir and pump functions (TEF and AEF), and a positive correlation of e’average with s’ wave (both septal and lateral walls) and the reservoir, conduit and pump LA functions. Conclusion An impairment of LA functions in Chagas cardiomyopathy was observed.

Função Atrial Esquerda em Pacientes com Miocardiopatia Chagásica Crônica

Background Chagas disease is a cause of dilated cardiomyopathy, and information about left atrial (LA) function in this disease still lacks. Objective To assess the different LA functions (reservoir, conduit and pump functions) and their correlation with the echocardiographic parameters of left ventricular (LV) systolic and diastolic functions. Methods 10 control subjects (CG), and patients with Chagas disease as follows: 26 with the indeterminate form (GI); 30 with ECG alterations (GII); and 19 with LV dysfunction (GIII). All patients underwent M-mode and two-dimensional echocardiography, pulsed-wave Doppler and tissue Doppler imaging. Results Reservoir function (Total Emptying Fraction: TEF): (p <0.0001), lower in GIII as compared to CG (p = 0.003), GI (p <0.001) and GII (p <0.001). Conduit function (Passive Emptying Fraction: PEF): (p = 0.004), lower in GIII (GIII and CG, p = 0.06; GI and GII, p = 0.06; and GII and GIII, p = 0.07). Pump function (Active Emptying Fraction: AEF): (p = 0.0001), lower in GIII as compared to CG (p = 0.05), GI (p<0.0001) and GII (p = 0.002). There was a negative correlation of E/e’average with the reservoir and pump functions (TEF and AEF), and a positive correlation of e’average with s’ wave (both septal and lateral walls) and the reservoir, conduit and pump LA functions. Conclusion An impairment of LA functions in Chagas cardiomyopathy was observed.