Influence of left ventricular hypertrophy on ventricular arrhythmias in hypertensive patients / 대한내과학회지

OBJECTIVES:Left ventricular hypertrophy(LVH) increases the risk of sudden death in hypertensive patients and this is known due to ventricular arrhythmias. Thus, author studied the relationship between LVH as a hypertensive target organ damage and ventricular arrhythmias. METHODS: 24-hour ambulatory electrocardiographic monitoring, measurement of microalbumin in 24-hour urine and fundoscopic examination were performed on 100 hypertensives (50 patients without LVH and 50 patients with LVH on EKG) who admitted Pusan National University Hospital. RESULTS: In patients with LVH, ventricular extrasystoles occurred more frequently than without LVH(p<0.05) and ventricular couplet and ventricular tachycardia were more common but statistically not different. Microalbuminuria and hypertensive retinopathy were more severe in patients with LVH than without LVH(p<0.05 and p<0.01, respectively). CONCLUSION: Of the ventricular arrhythmias, ventricular extrasystole but not ventricular couplet and ventricular tachycardia occurred more frequently in patients with LVH than without LVH. Thus, prospective study with long-term follow up should be done to establish the relationship between hypertensive LVH and cardiovascular mortality, especially sudden death. And, further study should be done to make the relationship between reduction in LVH with antihypertensive therapy and reduction in LVH-associated ventricular arrhythmias.

Heart Rate Variability in Mitral Valve Prolapse Syndrome

BACKGROUND AND OBJECTIVES: Studies in patients with mitral valve prolapse syndrome (MVPS) have shown the coexistence of various forms of autonomic dysfunction, and so this is an area that requires further investigation. METHODS AND MATERIALS: The study group consisted of 65 patients (36 men and 29 women), aged 16 to 43 years (mean+/-SD, 28+/-8) with symptomatic, echocardiographically proven mitral valve prolapse (MVPS) who were free of other organic heart diseases and arrhythmias. In a prospective study, heart rate variability (HRV) indexes were calculated from 24-hour Holter recordings obtained during normal daily activity and plasma norepinephine was measured, and then these data were compared among the study group according to clinic heart rate (HR). RESULTS: The study group was divided into below 60 bpm (group 1: n=13), 60 - 80 bpm (group 2: n=36) and over 80 bpm (group 3: n=16) on the basis of clinic HR. These patient groups were matched with respect to age and gender. There were significant difference in SDNNIDX, rMSSD and pNN50 between these groups (p=0.005, 0.009 and 0.002 respectively), and these HRV measures correlated inversely with clinic HR (p<0.01). As clinic HR increased, there was a tendency for plasma norepinephrine concentration to also rise (p<0.05), but there was no statistical significant difference between these groups. CONCLUSION: Our data suggests that MVPS may have subgroups of HRV, reflecting cardiac autonomic modulation, according to clinic HR.

Relation Between Pulmonary Hypertension and Mitral Stenosis Severity in Patients Undergoing Balloon Mitral Commissurotomy

BACKGROUND: In patients with mitral stenosis, the degree of pulmonary hypertension is expected to be related to the severity of mitral valve obstruction. However, some patients with severe mitral stenosis do not develop reactive pulmonary hypertension. MATERIALS AND METHODS: We evaluated 34 patients with symptomatic mitral stenosis undergoing percutaneous mitral valvuloplasty by clinical, echocardiographic, and invasive hemodynamic(cardiac cathrterization) data. Prevalvuloplasty data were available in 34 subjects[mean age 38+/-9 year ; women 74% ; NYHA class 1 (6 patients), class 2 (17 patients), class 3 (7 patients), class 4 (4 patients) ; in electrocardiography, NSR(23 patients), Atrial fibrillation(11 patients)]. RESULTS: 1) The pulmonary vascular bed gradient was significantly correlated with pulmonary vascular resistance(r=0.91), mean pulmonary artery pressure(r=0.82), transmitral mean pressure gradient(r=0.64) and mitral valve area(r=-0.48). The pulmonary vascular resistance was significantly correlated with mena pulmonary artery pressure(r=0.77), transmiral mean pressure gradient(r=0.61) and mitral valve area(r=-0.54), NYHA functional classification(r=0.36). However, the pulmonary vascular bed gradient and pulmonary vascular resistance was not significantly correlated with age, sex, cardiac output, the severity of mitral regurgitation and mean left atrial pressure. 2) The mean pulmonary artery pressure was significantly correlated with mean left atrial pressure(r=0.80), transmitral mean pressure gradient(r=0.72) and mitral valve area(r=-0.47). 3) When patients were divided into those with a pulmonary vascular bed gradient > 12mmHg and

A Study on Serum Magnesium Concentration in the Management of Congestive Heart Failure / 대한내과학회지

OBJECTIVES: There are many interesting reports suggesting that magnesium(Mg) deficiency is deleterious in patients with congestive heart failure (CHF). It is paradoxical that the most important cause of Mg deficiency in these persons is maybe use of therapeutics including diuretics. Authors investigated the trend of serum and 24 hour urine Mg with other relating electrolytes in Mg homeostasis prospectively, in the management of CHF. And we assessd the effects of medications and many variables in .CHF on serum Mg, and the usefulness of serum Mg representing the body content. METHODS: Fifty three patients who were diagnosed as CHF by clinical finding and echocardiogaphy were prescribed conventional doses of diuretics as furosemide 40mg and spironolactone 50mg daily, with or without angiotensin converting enzyme(ACE) inhibitor and digitalis. And then, serial serum and 24 hour urine Mg, sodium, potassium and calcium were obtained at admission, 2nd day, 5th day, and discharge. RESULTS: The patients group with chronic CHF, which was defined as long-term use of diuretics over 6 months, showed higher prevalence of low level of serum Mg concentration than the group with acute one(11 of 28, 39% vs. 2 of 25. 8%, P< 0.01). Of those two groups, the latter showed upward trend of serum Mg from admission to discharge, but the former showed no change. In 24 hour urine Mg excretion, the amount of the patients with CHF was larger than that of control group. In the chronic CHF group, the effect of digitalis on decreasing serum Mg was evident. Serum Mg of acute CHF group correlated with serum BUN(r=0.5609). Whereas, that of chronic group with ejection fraction(r=-0.4742) and plasma renin activity(r=-0.3791), with serum potassium(r=0.4673) and creatinine(0.5846). Serum Mg may be useful indicator of Mg homeostasis, especially in chronic CHF patients. CONCLUSION: Because patients with chronic CHF were prone to deficiency of Mg in the management, maintaining the adequate serum Mg through long- term replacement seems very important in decreasing the morbidity and mortality of these persons.

Distribution of HDL Cholesterol and LDL Cholesterol in Healthy Normal Korean Adults

BACKGROUND: This study was designed to estabilish serum LDL cholesterol(LDL-C) and HDL cholestrol(HDL-C) levels in the Korean adult population and to identify the difference in sex, age, and living place and the incidence of high risk group and the affecting factors on the serum lipid levels. METHODS: The serum LDL-C and HDL-C distribution in the normal Korean abult population were studied in 5,278 cases(males 2,802 and females 2,476) in the age groups of 3rd to 8th decade. Data were collected from 33 institutes and hospitals throughout the country during the period of June 1989 to December 1990. The serum Lipid levels were examined in the state of fasting of at least 12 hours. Total cholesterol and triglyceride levels were measured by enzymatic assays and HDL-C levels were determined by precipitation methods. The level of LDL-C was determined indirectly using the formula by Friedwald [LDL-C=total cholesterol-(HDL-C+triglyceride/5)]. RESULTS: The mean level of LDL-C was 112.1mg/dl. Males had 110.0mg/dl and females had 114.5mg/dl without statistical significance between gender, but levels were significantly higher in the 4th decade in males and in the 6th, 7th and 8th decade in females. The LDL-C levels rose gradually with the increase of age. The peak level of LDL-C for the males was in the 7th decade and that for the females was in the 8th decade. The mean level of serum HDL-C was 45.1mg/dl. Males had 43.8mg/dl and females had 46.6mg/dl without statistical significance between gender, but levels were significantly higher in the 3rd, 4th, 5th and 6th decade in females. The incidence LDL-C level of > or = 160mg/dl was 10.0%. Males had 8.2% and females had 12.1% with significantly higher incidence in females, especially in 6th decade females. The incidence of LDL-C level of > or = 160mg/dl of big cities was 10.7% and that of smaller cities & towns was 8.8% with significantly higher incidence in big cities. But, there was no significant difference in gender between big cities and smaller cities & towns. The incidence of LDL-C level of > or = 160mg/dl was significantly higher in 7th decade males in big cities and that of big cities and smaller cities and smaller cities & towns was 15.9% and 5.2%, respectively. The incidence of HDL-C level of <35mg/dl was 17.4% Males had 20.0% and females had 14.5% with significantly higher incidence in males, especially in 4th decade males. The incidence of HDL-C level of <35mg/dl of smaller cities & towns was 19.8% and that of big cities was 16.2% with significantly higher incidence in smaller cities & towms. Males in smaller cities & towns had 23.1% and males in big cities had 18.1% with statistical higher in smaller cities & towns. But, there was no significant difference in females between big cities and smaller cities & towns. The incidence of HDL-C level of <35mg/dl was significantly higher in 4th and 6th decade males in smaller cities & towns and that of smaller cities & towns and big cities was 26.8%, 25.6% and 16.2%, 17.7%, repectively. The significantly positively related factors for serum LDL-C level were age, BMI, systolic blood pressure(SBP), location and occupation. And those for serum HDL-C level were SBP and family history and negatively related factor for HDL-C level were BMI, smoking, and exercise. CONCLUSION: This study can provide the basic date base for prevention and management of coronary heart disease among Korean population.

Plasma Glucose, Insulin and C-Peptide in Essential Hypertension

BACKGROUND: High blood pressure is prevalent in obesity and diabetes, especially noninsulin dependent diabetes mellitus, and both conditions are insulin resistant state. METHOD: To test whether resistance to insulin-stimulated glucose uptake and hyperinsulinemia are involved in the pochogenesis of hypertension, author measured glucose, insulin and C-Peptide reponse after oral glucose loading in 52 cases of essential hypertension and 62 cases of normal controls who had been admitted to the ward of internal medicine, Pusan National University Hospita. RESULTS: Basal plasma glucose, insulin and C-Peptide levels in control subjects were 92.1+/-36.8mg/dl, 8.7+/-5.5microu/ml and 2.2+/-1.8ng/ml and in hypertensive subjects were 95.7+/-32.6mg/dl, 12.2+/-5.3microu/ml and 2.9+/-1.6ng/ml. The basal insulin level was markedly higher than tat of control subjets (p<0.05). The basal glucose and C-Peptide levels in hypertensive patioents were higher than controls but statistically not significant. Plasma glucose levels in time course after glucose load in hypertensive patients showed significantly higher levels in 60,90minutes than controls. Plasma insulin levels in hypertensives in 90 minutes were significantly higher. The C-Peptide levels in hypertensives showed significantly higher in each times 30,60,90,120 minutes than controls. In hypertensive patients, body weight, blood pressure levels and duration of hypertension were not significantly correlated with responses of glucose, insalin and c-peptioce. Hypertensive patients aboce the age of 50 showed significantly higher glucose levels in 60,90,120 minutes than under age of 50. CONCLUSION: These results indicate some tendency of disturbed glucose turnover or insulin-resistant state in essential hypertension. This metabolic disturbance in essential hypertension should be considered in the management of hypertensive patients.