Effect of angiotensin-converting enzyme gene polymorphism on left ventricular remodeling after anteroseptal infarction

BACKGROUND AND HYPOTHESIS

Genetic influence on cardiac remodeling is uncertain. The purpose of this study is to determine the effects of polymorphism of the angiotensin-converting enzyme (ACE) gene on cardiac remodeling after myocardial infarction.

METHODS

The subjects were 43 patients with old anteroseptal myocardial infarction. Based on the polymorphism of the ACE gene, they were classified into a deletion group of 25 patients (D/D genotype in 4 and D/I genotype in 21) and an insertion group of 18 patients (all I/I genotype). Echocardiograms were used to determine left ventricular end-diastolic and end-systolic diameters, interventricular septal and posterior wall thicknesses, left ventricular mass, left atrial diameter, and left ventricular ejection fraction. Blood concentrations of atrial and brain natriuretic peptide were also measured.

RESULTS

Left ventricular end-systolic and end-diastolic dimensions, left ventricular mass, and levels of both atrial and brain natriuretic peptide were significantly higher in the deletion group. In contrast, septal thickness, posterior wall thickness, and ejection fraction showed no differences between the two groups.

CONCLUSIONS

In patients with old anteroseptal infarction, ACE gene polymorphism of the D/D and D/I genotypes has a stronger influence on left ventricular remodeling than polymorphism of the I/I genotype.

Influence of angiotensin-converting enzyme gene polymorphism on development of athlete's heart

BACKGROUND AND HYPOTHESIS

Genetic influence on development of athlete's heart is uncertain. This study investigated whether angiotensin-converting enzyme (ACE) gene polymorphism influenced development of athlete's heart.

METHODS

Forty-three participants in a 100-km ultramarathon were classified on the basis of ACE gene polymorphism into a deletion group (n = 26) and an insertion group (n = 17). Echocardiograms were recorded to determine left ventricular end-diastolic and end-systolic diameters, interventricular septal thickness, left ventricular posterior wall thickness, left ventricular mass, and ejection fraction.

RESULTS

Left ventricular end-diastolic diameter (65.5 +/- 4.0 mm) and left ventricular mass (369.5 +/- 73.9 g) were significantly larger in the subjects with deletion than in those with insertion (57.4 +/- 4.2 mm, 306.5 +/- 93.7 g). However, no significant differences in the other parameters were noted.

CONCLUSIONS

In long-distance runners, ACE gene polymorphism of the D/D and D/I genotypes has a stronger influence on left ventricular hypertrophy than polymorphism of the I/I genotype.

Assessment of reflection pulse wave in patients with cardiomyopathy: evaluation of noninvasive measurement of wave intensity

OBJECTIVE

We assessed the reflection pressure wave using noninvasive measurement of wave intensity (WI) in patients with cardiomyopathy.

METHODS AND RESULTS

Subjects included 8 patients with hypertrophic cardiomyopathy (HCM group) and 10 patients with dilated cardiomyopathy (DCM group). Twelve healthy subjects were used as a control group. By using a combined Doppler and echo-tracking system, changes in vascular diameter (dD) and blood flow velocity (dV) were recorded simultaneously at the common carotid artery and dD x dV was measured as WI. In the components of WI, the positive component of early systolic phase (FE) and the negative component following FE (B) were significantly reduced in the DCM group. There was a significant positive correlation between FE and B in all 3 groups. The appearance time of B was significantly shorter in the HCM group and significantly longer in the DCM group compared with the control group.

CONCLUSIONS

It was suggested that the value of the reflection pressure wave was influenced by the left ventricular contractility, and that the effect of the reflection pressure wave appeared earlier in patients with HCM and later in patients with DCM compared with the control subjects.

Time- and subunit-dependent differential mRNA expression of L-type Ca2+ channel during progression of right ventricular hypertrophy

To clarify the molecular basis for changes in L-type calcium channel (VLCC) density in ventricular hypertrophy, we analyzed the mRNA expression of all the subunits including the main subunit alpha1c and auxiliary subunits (alpha2delta, beta2 and beta3) composing VLCC in rat right ventricular hypertrophy (RVH) induced by monocrotaline injection. To test the hypothesis that the expression of each subunit might change differently during progression of RVH, leading to an altered electrophysiologic outcome for VLCC, we investigated the ratio of the mRNA level of each auxiliary subunit to the main subunit. After monocrotaline injection, alpha1c mRNA showed a transient decrease on the 14th day and thereafter significantly increased to reach approximately 1.8 fold that of the control level on the 21st day. The auxiliary subunit alpha2delta mRNA showed a pattern similar to that of alpha1c. The beta3 mRNA increased rapidly after monocrotaline injection and increased approximately 4.1 fold. On the other hand, beta2 mRNA showed no significant changes. Accordingly, only the mRNA ratio of beta3 to alpha1c showed a significant increase among the auxiliary subunits after the monocrotaline injection. The ratio increased to a maximum of approximately 5.7 fold on the 14th day and thereafter decreased. These results suggest that VLCC density may be modified not only by alpha1c but also by its auxiliary subunit expression in ventricular hypertrophy, and provide a clue for understanding the controversial electrophysiologic results on VLCC density in hypertrophied hearts.

Spatial and temporal analysis of left ventricular filling flow propagation in hypertensive patients before and after regression of myocardial hypertrophy with alacepril therapy

The purpose of this study was to assess the clinical significance of spatial and temporal analysis of left ventricular (LV) filling-flow propagation using color M-mode Doppler echocardiography before and after regression of LV hypertrophy in patients with hypertension. Seven patients with hypertensive LV hypertrophy were studied. Echocardiographic and Doppler examinations were performed both before and after 6 months administration of alacepril. LV mass index (LVMI), LV flow propagation velocity (FPV), and the maximal early transmitral flow velocity (E) were measured. LVMI, FPV, and FPV/E ratio were compared to before and after administration of alacepril. In addition, the correlation between LVMI and FPV/E ratio was evaluated. Results showed that LVMI was significantly decreased (P < 0.05) and the FPV/E ratio was significantly increased (P < 0.05) after treatment with alacepril. There was no significant change in FPV. In addition, there was a significant negative correlation between LVMI and the FPV/E ratio (r = -0.662, P < 0.001). The present study indicates that the FPV/E ratio could be a useful noninvasive parameter to assess the diastolic dysfunction associated with LV hypertrophy in patients with hypertension.

[A case of an advanced aged Eisenmenger's syndrome]

We report a 70-year-old women with Eisenmenger's syndrome. Eisenmenger's syndrome with ventricular septal defect was diagnosed at another hospital when she was 32 years old. Then, she was referred to our hospital at age 60 old and she now is according to the out patient in over clinic. She have mild cardiac function, NYHA classification, was II-M, polycythemia cell blood count 535 x 10(4) and 17.2 g/dl in hemoglobin. Echocardiography suggested serious Eisenmenger's syndrome. The left ventricle was compressed, the blood pressure of the right ventricle exceeded 105 mmHg, and the onset of the right to left shunt flow was thought to be 250 msec bored on the electrocardiogram Q wave. The reason why the progression of complicated obstructive pulmonary artery disease was slow may have been become of the mildness of her polycythemia, and this is presumed to be the reason for her long survival to age 70.

Acute myocardial infarction induced by alternating exposure to heat in a sauna and rapid cooling in cold water

We describe a patient with acute myocardial infarction, which was thought to result from plaque rupture or thrombosis because of coronary artery spasm. The vasospasm was most likely induced by stimulation of the alpha-adrenergic receptors during alternating heat exposure during sauna bathing and rapid cooling during cold water bathing. This report emphasizes the dangers of rapid cooling after sauna bathing in patients with coronary risk factors.

[Cardiac amyloidosis]

In our experience, QS pattern of poor R wave progression and atrio-ventricular block of varying degrees on electrocardiogram, cardiomegaly with pleural effusion on chest X-ray film, left ventricular wall thickening, pericardial effusion and findings suggesting left ventricular diastolic dysfunction on echocardiogram and increased right ventricular end-diastolic pressure in cardiac catheterization were frequently observed in patients with cardiac amyloidosis. Though none of these findings are specific, we should suspect cardiac amyloidosis as a possibility when some of these signs are observed in patients with chronic cardiac failure of unknown etiology. Left ventricular mass obtained from echocardiography could be useful predictive parameter of prognosis in patients with cardiac amyloidosis.

Purulent pericarditis due to group B streptococcus and mycotic aneurysm of the ascending aorta: case report

A 61-year-old female, with a history of uterine and cervical cancer treated with radical hysterectomy and 2 years of postoperative chemotherapy, presented to the emergency department with dyspnea on exertion. Computed tomography of the chest revealed a large pericardial effusion and a sacciform aneurysm of the ascending aorta. The patient subsequently underwent emergency pericardiocentesis with drainage of approximately 330 ml of a bloody and turbid effusion. Cultures from the effusion yielded group B streptococcus. Multiple organ failure and disseminated intravascular coagulation syndrome occurred in the acute phase, but gradually improved with continuous antibiotic therapy. On the 194th hospital day, in situ reconstruction of the ascending aorta was successfully performed using a synthetic graft. Although rarely reported, both purulent bacterial pericarditis and mycotic aneurysm can be life-threatening.

[Assessment of localized hypertrophy in the basal part of the interventricular septum in the elderly]

The basal part of the interventricular septum (IVS) is known to show different hypertrophic features from those observed in the other parts of the left ventricular wall. These are considered to reflect physiological changes that occur with normal aging. However, these changes have not been carefully evaluated, and their clinical significance has not been defined. We assessed these changes echocardiographically. The subjects were patients at least 70 years of age in whom localized hypertrophy in the basal part of the IVS was seen during the whole cardiac cycle on echocardiography. The prevalence was 6.3% among 96 consecutively studied patients. All 6 patients had a history of hypertension. Echocardiographic findings were as follows: 1) the left atrium was mildly or moderately dilated, 2) there was no evidence of either dilatation or narrowing of the left ventricular cavity, 3) the left ventricular wall motion appeared normal and indices of systolic function were within normal limits in all subjects except one who had a history of myocardial infarction, 4) the angle formed by the aorta and the IVS averaged 106.7 degrees (range: 95 to 120 degrees), 5) Doppler examination showed increases in the ratio of the peak flow velocity during atrial systole to the peak flow velocity early in diastole, and 6) prolongation of the deceleration time of the flow velocity early in diastole. The last of these findings suggested left ventricular diastolic dysfunction, but peak flow velocity at the left ventricular outflow tract was normal. There was no evidence of stenosis of the left ventricular outflow tract. Localized hypertrophy in the basal part of the IVS in elderly patients could be a type of cardiac hypertrophy caused by hypertension. On echocardiography, the basal part of the IVS seemed to protrude toward the left ventricular cavity, but there was no evidence of stenosis in the left ventricular outflow tract.

Heart failure in 3 patients with acromegaly: echocardiographic assessment

We evaluated 3 patients with acromegaly who developed heart failure. Heart failure appeared to be due to acromegalic cardiomyopathy in 2 patients who did not have hypertension or evidence of coronary artery disease, and it was possibly due to acromegalic cardiomyopathy combined with familiar hypertrophic cardiomyopathy in 1 patient. The common echocardiographic findings in the present three cases were: 1) enlargement of the left atrium, 2) markedly dilated left ventricular cavity with diffuse hypokinesis, 3) decrease of indices of the left ventricular systolic function, and 4) no evidence of left ventricular hypertrophy. Echocardiographic findings in acromegaly with congestive heart failure resemble those of idiopathic dilated cardiomyopathy.

Assessment of posterior aortic wall motion using echocardiogram in patients with atrial fibrillation

BACKGROUND AND HYPOTHESIS

Noninvasive evaluation of left ventricular (LV) diastolic function was performed on 12 patients with atrial fibrillation (AF) using posterior aortic wall echocardiogram and a parameter for determining the optimal heart rate in patients with chronic atrial fibrillation was considered.

METHODS

Subjects were divided into two groups; one with no underlying cardiac disease (AF only group; n = 7) and the other with dilated cardiomyopathy (DCM group; n = 5). Left atrial emptying index (LAEI) obtained from the posterior aortic wall echocardiogram was used as the parameter of LV diastolic function, and R-R interval-LAEI relation and minimum R-R interval showing LAEI = 1.0 were investigated and compared between the two groups.

RESULTS

There was a good correlation between R-R interval and LAEI until LAEI of 1.0 was obtained in all patients. Slope of the regression line was significantly steeper in the AF only group than in the DCM group, and minimum R-R interval showing LAEI = 1.0 was significantly shorter in the AF only group.

CONCLUSION

Assessment of R-R interval-LAEI relation was useful for the noninvasive evaluation of LV diastolic function, and this parameter could be used for clinical application to determine the optimal heart rate in atrial fibrillation.

The effect of beta-adrenergic blockade in dilated cardiomyopathy--a questionnaire study in Japan

The effect of beta-blockade in dilated cardiomyopathy was studied by a questionnaire survey. Thirty-three cases were monitored in whom metoprolol (22 patients, 35.9 +/- 20.4 mg, mean +/- SD), propranolol (four patients, 26.3 +/- 7.5 mg), or other beta-blockers (seven patients) were administered. Four patients died, but no direct relationship was found between administration of beta-blocker and death. The NYHA functional class improved significantly. The mean heart rate decreased from 96/min to 77/min (P less than 0.01). The mean cardiothoracic ratio decreased from 55.6% to 52.1% (P less than 0.01). The mean ejection fraction of the left ventricle measured by echocardiogram increased from 30.4% to 36.9% (P less than 0.01). Exercise tolerance in the treadmill test improved significantly. There was no change in blood pressure, nor were there arrhythmias seen on Holter electrocardiograms. In two patients, congestive heart failure deteriorated after administration of beta-blockers. It is concluded that beta-adrenergic blockade has a beneficial effect in most of the patients with dilated cardiomyopathy.

[A case of Vietnamese immigrant with tuberculous mediastinopericarditis]

A case of vietnamese immigrant with tuberculous mediastinopericarditis was reported and the literature was reviewed. A 39 year-old man was admitted to our hospital with chief complaints of dyspnea and weakness. Blood chemistry suggested the existence of congestive liver dysfunction. Chest X-ray film revealed marked cardiomegaly and a abnormal mass in the anteriorly superior area which was confirmed as anterior mediastinum on CT scan. Echocardiogram disclosed a large volume of pericardial effusion and thickened pericardium. Tuberculin test was positive. Firstly, this mediastinal mass was believed to be malignant tumor and the pericardial effusion had originated from it. Finally, tuberculous mediastinopericarditis was diagnosed by detecting tuberculous mycobacterium from the cultured pericardial effusion and also the biopsied lymph nodes. Although occurrence of tuberculous mediastinopericarditis is rare at the present time in Japan, this disease has not been exterminated and should be kept in mind.