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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The surface electrocardiogram remains an insensitive method for detection of ventricular hypertrophy. Technical problems related to body size and habitus and distance from the heart cannot be overcome. Coronary arterty disease and amyloidosis, although frequently associated with hypertrophy, tend to obscure the electrocardiographic changes because of the attendant loss of voltage. The progress made in the last 20 years is due primarily to re-evaluation of traditional criteria in terms of careful anatomic correlation. The studies cited have the advantage of using specific clinical diagnoses in a defined population, specific chamber weights, and a 97.5 percentile confidence level for distinguishing normal pathologic and electrocardiographic data from abnormal. They are limited because the results may not apply to females or patients with mitral stenosis and congenital heart disease. In general, the electrocardiogram can be expected to detect left ventricular hypertrophy in six out of ten patients with the disease, and will misdiagnose the problem in about one out of every ten without the disease. Methodology using multiple criteria will achieve the best sensitivity and specificity. Several methods are available and of comparable accuracy. Simplicity of these methods varies widely and will be a factor in the choice of the method selected. The electrocardiogram will perform best in the population of patients with hypertension and aortic stenosis or regurgitation and have its greatest limitation in patients with coronary artery disease and myocardial infarctions. Echocardiography is proven to be more sensitive than the electrocardiogram for detection of left ventricular hypertrophy. Sensitivity is around 90 per cent with 95 per cent specificity. Its major limitations lie in the expense as compared to the electrocardiogram and in inadequate image resolution in a small proportion of patients. In order to achieve the results reported by centers proficient in this technique, careful attention must be paid to precise standardization of measurements and selection of images to be measured. When this is done the echocardiogram certainly offers a distinct advantage over the electrocardiogram in detecting left ventricular hypertrophy. We recommend the use of left atrial abnormality as a criterion to diagnose left ventricular hypertrophy when there is right bundle branch block. When left bundle branch block is present on the electrocardiogram, traditional criteria are probably no more accurate than the bundle branch block itself.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Recent progress in the electrocardiographic diagnosis of ventricular hypertrophy. 296 47

To assess the effect of short-term alteration of left atrial pressure and volume on the circulating plasma level of atrial natriuretic factor, 11 patients with left atrial hypertension due to mitral stenosis were studied at the time of percutaneous balloon mitral valvuloplasty. Hemodynamic measurements and plasma atrial natriuretic factor levels were obtained before, immediately (5 to 10 min) after and 24 h after valvuloplasty, and echocardiographic left atrial size was determined before and 24 h after valvuloplasty. Immediately after valvuloplasty, left atrial pressure decreased from 28 +/- 2 to 10 +/- 1 mm Hg (p less than 0.0005), mitral pressure gradient decreased from 20 +/- 2 to 7 +/- 1 mm Hg (p less than 0.0005), mitral valve area increased from 0.8 +/- 0.1 to 1.9 +/- 0.2 cm2 (p less than 0.0005) and plasma atrial natriuretic factor level rose from 249 +/- 42 to 348 +/- 50 pg/ml (p less than 0.01). This short-term rise in atrial natriuretic factor level may reflect a transient increase in left atrial pressure associated with balloon occlusion of the mitral valve.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Responsiveness of plasma atrial natriuretic factor to short-term changes in left atrial hemodynamics after percutaneous balloon mitral valvuloplasty. 296 28

The bronchial venous system closely communicates with the pulmonary circulation. To assess the changes in the bronchial circulation in chronic pulmonary venous hypertension, fiberoptic bronchoscopy and right heart catheterization were performed in 31 patients with mitral stenosis. Nonpulsatile submucosal vessel dilatation, consistently seen in all patients and called the vessel dilatation score, was assessed visually by three independent bronchoscopists. The vessel dilatation score was correlated more closely with pulmonary artery wedge pressure (r = 0.687) (p less than 0.001) than to mean pulmonary artery pressure (r = 0.531) (p less than 0.01) and right atrial pressure (r = 0.178) (NS). The vessel dilatation score decreased after reduction of the left atrial load by surgery. These results suggest that the dilated vessels observed in patients with mitral stenosis are bronchial veins that are engorged secondary to increased blood flow via bronchopulmonary anastomoses.
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PMID:Endobronchial changes in chronic pulmonary venous hypertension. 319 55

A total of 458 cases (11.5%) with valvular heart diseases in the aged (greater than or equal to 60 years) were found among 4,000 consecutive autopsies. They included 204 cases (45%) of aortic regurgitation (AR), 171 cases (37%) of mitral regurgitation (MR), followed by 45 (10%) of aortic stenosis (AS) and 27 cases (6%) of mitral stenosis (MS). As an etiology of the valvular diseases, degenerative type was found in 195 cases (43%), ischemic origin in 91 cases (20%), followed by inflammatory origin such as syphilitic in 51 and infective endocarditis in three, aortitis in two and rheumatic in 49 (11%). Congenital origin was also found in 18 cases (4%). Among various types of valvular diseases in the aged, degenerative AR was most frequently found in 140 cases, followed by MR due to papillary muscle dysfunction in 91 cases. The clinical characteristics in cases with valvular diseases were as follows: atrial fibrillation was prominent in MS; congestive heart failure was found in 60% of cases except those with degenerative AR; cardiac death was frequent in syphilitic and rheumatic AR; association of hypertension was found in 50% of cases with MR and degenerative AR. In this article the characteristics of the valvular heart disease in the aged and additionally its diagnosis and treatment were discussed.
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PMID:[Valvular heart diseases in the aged]. 327 12

It has been reported that a patient with atrial fibrillation (AF) is in the hypercoagulable state and that this state results in a high incidence of systemic thromboembolisms. In this paper, we have investigated plasma fibrinopeptide A (FPA) levels and the effects of subcutaneous administration of heparin on these levels in patients with AF. Forty-five patients with hypertension (HT) or mitral stenosis (MS) were classified into four groups according to whether they had AF complications; i.e. HT with normal sinus rhythm (NSR), HT with AF, MS with NSR and MS with AF. Patients with AF demonstrated significantly higher plasma FPA levels and lower plasma antithrombin III (AT III) activities than those with NSR. When low dose heparin was administered to patients with AF, plasma FPA levels were decreased to the near normal range, accompanied by an increase in heparin-AT III complex activity and heparin concentration 0.5-1.0 h after injection. These levels were maintained for 5 h. From these results it was concluded that patients with AF were in the hypercoagulable state and that the measurement of plasma FPA levels provided a possibility to detect the underlying activation of blood coagulation.
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PMID:Fibrinopeptide A (FPA) levels in atrial fibrillation and the effects of heparin administration. 336 96

Closed mitral valvotomy for rheumatic mitral stenosis was performed on 126 pregnant women (average duration of pregnancy c. 21 weeks), 91% of whom were in NYHA functional class III or IV. Associated functional tricuspid regurgitation was present in 47 (37%) of the women, and 102 (81%) had critical mitral stenosis (digitally assessed valve area less than 1 cm2). There was no surgical mortality. Postoperatively 84% of the women were in NYHA class I. Clinical evidence of pulmonary artery hypertension and tricuspid regurgitation regressed postoperatively in most patients. Full-term normal delivery was achieved in 82% of the pregnancies, with total fetal mortality 6%. There were no congenital abnormalities and the infants' progress was normal. At 5-year follow-up 86% of the women were in NYHA class I or II and at 10 years the figure was 60%. The restenosis rate was 2%/year and the late mortality 3.3%. Closed mitral valvotomy during pregnancy thus was safe and reliable, giving significant functional and clinical improvement without adversely affecting the fetus.
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PMID:Closed mitral valvotomy during pregnancy. A 20-year experience. 338 43

Cardiac function is difficult to assess in patients with atrial fibrillation due to the widely fluctuating cycle lengths resulting in variable ventricular hemodynamics. With respect to ECG-gated blood pool scintigraphy, distortion of the time activity curve occurs due to a summation of irregular cycle lengths. Therefore, performing such a study has been regarded meaningless. To evaluate left ventricular function during atrial fibrillation using scintigraphic technique, a new processing algorithm was devised to make multiple gated images which are discriminated by the preceding R-R interval, and left ventricular filling and function curves were established. The left ventricular filling curve, obtained by plotting end-diastolic volume against the preceding R-R intervals demonstrated an impairment of blood filling in cases of mitral stenosis and constrictive pericarditis, which resolved after mitral commissurotomy in case of mitral stenosis. The left ventricular function curve, established by plotting stroke volume against end-diastolic volume, was analyzed according to indices such as "slope" and "position". Both of these indices were significantly reduced in relation to the severity of heart failure according to the NYHA's functional classification and cardiomegaly on chest radiography. On individual comparisons of underlying diseases, the indices decreased in the following order; lone atrial fibrillation, hyperthyroidism, aging, hypertension, mitral valve disease, ischemic heart disease, dilated cardiomyopathy and aortic regurgitation. The indices correlated closely with ejection fraction. In cases of mitral regurgitation, however, the function curves were situated to the right and above those of lone atrial fibrillation and decreased in slope despite the fairly well-maintained ejection fraction. After treatment with digitalis and/or diuretics, the function curves shifted to the left and upward. In conclusion, left ventricular filling and function curves based on a newly-devised algorithm of ECG-gated blood pool scintigraphy are of considerable clinical value in evaluating cardiac performance in patients with atrial fibrillation. They are widely applicable to the assessment of therapeutic and interventional effects.
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PMID:[Left ventricular function during atrial fibrillation assessed by left ventricular function curve using ECG-gated blood pool scintigraphy]. 350 42

Sixty one patients were studied that were subjected to mitral valvular prosthesis--28 patients with pure or prevailing mitral stenosis, 12 with pure or prevailing mitral insufficiency and 21 patients with degree competitive stenosis and insufficiency. The patients, to have mitral valvular prosthesis, undergo the operation, most often, in the presence of pronounced pulmonary capillary and arterial hypertension and preserved right-ventricular and left-ventricular function. The pulmonary hypertension is with the highest values in the patients with mitral stenosis leading. In the patients with leading stenosis, passes of compromised right-ventricular function could be established. The cases with disturbed left-ventricular function are from the groups with prevailing mitral insufficiency or competitive stenosis and insufficiency. The time for mitral valvular prosthesis should be selected so as not to allow the manifestation of bilateral cardiac insufficiency as well as the formation of essential pulmonary disorders.
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PMID:[Preoperative clinical and hemodynamic characteristics of patients with mitral valve defects subjected to valve prosthesis]. 361 4

Exercise limitation is common in patients with chronic pulmonary venous hypertension. One postulated mechanism is ventilation-perfusion inequality secondary to vascular congestion and edema formation. To investigate this possibility, five patients with symptomatic, chronic mitral stenosis were studied at rest, during 10 min of steady-state exercise and during recovery from exercise. Both conventional indices of gas exchange and the multiple inert gas elimination method were used. Hypoxemia was not present in patients at any stage in the study and negligible shunt or low VA/Q lung units were demonstrated by the inert gas method. Instead, regions with high VA/Q ratio appeared toward the end of exercise and immediately after exercise. We postulate that this was the result of a marked redistribution of pulmonary blood flow, possibly due to an accumulation of interstitial edema fluid. It is concluded that the excessive ventilatory response to exercise observed in patients with mitral stenosis may, in part, be explained by an unequal distribution of ventilation and perfusion.
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PMID:The effects of exercise on ventilation-perfusion relationship in patients with mitral stenosis. 373 Jun 41

A total of 18 patients with pure rheumatic mitral stenosis between the ages of eight and 14 years (average 11.8 years) were studied. Left ventricular angiograms in the right anterior oblique view were obtained in each. Moderate to severe pulmonary arterial hypertension was present in all but one. The mean left ventricular end-systolic volume index was 25.4 +/- 8.5 ml/m2; it was increased in five patients. The mean left ventricular end-diastolic volume index was 64 +/- 13.5 ml/m2. It was normal in all except one patient, in whom it was increased to 91 ml/m2. The left ventricular stroke volume index, 39.6 +/- 8.8 ml/m2, was within the normal range. The left ventricular stroke volume index, 39.6 +/- 8.8 ml/m2, was within the normal range. The mean left ventricular ejection fraction was 0.61 +/- 0.09 ml, with a range of 0.44-0.72. The mean left ventricular ejection fraction was lower than normal (P less than 0.05). The ejection fraction was low in five of the 18 patients. Four of the five patients with an ejection fraction below 0.60 had severe pulmonary arterial hypertension. There was no correlation between the ejection fraction and left atrial pressure or the mitral valve area. Segmental contraction analysis in the five patients with a low ejection fraction showed global hypokinesia in four and segmental hypokinesia, involving predominantly the posterobasal segment, in one patient. Our study suggests that even children with pure mitral stenosis may have left ventricular dysfunction in the absence of active carditis.
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PMID:Left ventricular function in isolated rheumatic mitral stenosis in children. 374 34


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