Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The interpretation of IE recorded in children has been hampered by a lack of agreement regarding normal values. We recorded IE in 158 children and young adults (ages, three days to 33 years) to define the various conduction intervals in normal and disease states. The HBP was recorded in 156 subjects. In 85 subjects with normal conduction indicated by surface ECG, including 19 subjects with normal hearts, there were no statistically significant age-related differences in internodal, A-V nodal, or His-Purkinje conduction intervals. Therapeutic levels of digitalis did not alter the conduction intervals. In 11 subjects with first degree A-V block and in five subjects with congenital complete A-V block, the site of block as determined by IE could not be predicted from the surface ECG. No abnormalities in conduction intervals were found in 18 subjects with right bundle branch block (surgically induced in 17 cases). Intracardiac electrography with recording of the HBP was found to be a safe, informative technique for electrophysiologic investigations in children and young adults.
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PMID:Intracardiac electrography in children and young adults. 4 75

The experience with bundle branch block at the USAF School of Aerospace Medicine was reviewed. The clinical and follow-up status was evaluated in 394 subjects with right bundle branch block (RBBB) and 125 subjects with left bundle branch block (LBBB). The majority of subjects were asymptomatic at the time of bundle branch block diagnosis. The subjects were divided into subfroups based on electrocardiographic (EEG) findings to determine if any one subfroup was at higher risk for initial or follow-up morbidity of cardiobascular disease or follow-up mortality. At initial diagnosis and clinical evaluation, 94% of RBBB and 89% of LBBB subjects had no evidence of cardiobascular disease. In the RBBB group, 3 and 2% had cornary heart disease and hypertension, respectively; in LBBB subjects, 9 and 7% had cornary heart disease and hypertension, respectively. No one ECG subfroup in either the RBBB or LBBB group had a higher incidence of cardiobascular disease. Complete follow-up information was available in 94% of the RBBB subgroup subjects and 91% of the LBBB group. In the follow-up period, new cases of coronary heart disease and hypertension occurred in 6% of the RBBB group and 5 and 8%, respectively, in the LBBB group. Fourteen (4%) RBBB and nine (8%) LBBB subjects died during the follow-up period. No differences for follow-up groups. Progressive electrical dysfunction in the form of complete heart block occurred in one subject each absence, and degree of associated cardiobascular disease. Furthermore, within the age limits of the present aeromedical implications of bundle block are discussed.
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PMID:A clinical and follow-up study of right and left bundle branch block. 113 86

This phonocardiographic-echocardiographic study was based on measurement of the interval between the aortic component of the second sound (IIA) and the peak of the E wave of the mitral echogram. The study was performed in 20 cases of left bundle branch block (LBBB), 10 cases of right bundle branch block (RBBB), 10 cases of old myocardial infarct (MI), and 10 cases of systemic hypertension (HY). All patients were above 60 years of age, and their data were compared with those of old persons without evidence of heart disease serving as controls. The IIA-E interval was found markedly prolonged in LBBB, less prolonged in MI and RBBB, and was shortened in HY. A dynamic analysis revealed that this interval results from the isovolumic relaxation period (IRP) of the left ventricle plus the "opening time" of the mitral valve. The changes observed were explained as resulting from a modification of the IRP that should be correlated with a similar modification of the isovolumic contraction time. Myocardial fibrosis would cause prolongation of IRP through structural lesions while hypertension would cause abbreviation of IRP through hormonal effects modifying both contraction and relaxation.
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PMID:Ventricular relaxation and mitral opening time in various ventricular conditions of old age. 121 36

A prospective study of electrocardiograms (ECG's) was carried out on 102 adult hypertensive African patients at the Kenyatta National Hospital. Their mean age was 45.2 years. All the patients had normal sinus rhythm. Forty seven percent of the patients had sinus bradycardia, although this could be attributable to the drugs they were taking. The duration of the P wave increased with the severity of hypertension. Twenty five percent of the patients had evidence of first degree A-V block. This was an expected finding as most of the patients were on treatment with B-adrenoreceptor blocking agents. Two patients had LBBB and none had RBBB. There were 13 patients with evidence of left axis deviation (LAD) and the incidence increased with the severity of hypertension. S-T, T changes were noted in 12.8% and 29% of patients respectively. Q-Tc duration did not increase with severity of hypertension. Left ventricular hypertrophy was noted in 27.5% of the patients using the criteria devised by Romhilt et al.
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PMID:A prospective study of electrocardiographic features in adult black hypertensive patients at the Kenyatta National Hospital, Nairobi. 168 72

QRS intervals in the ECGs of members of the Framingham Heart Study cohort and offspring were measured to provide an estimate of the prevalence of intraventricular block in the general population. Intervals of greater than or equal to 0.09 second appear in men twice as commonly as in women, are rare before age 50 to 60, and shift from a predominance of right bundle branch block in the young to an indeterminate pattern in the elderly. Complete intraventricular block (QRS interval greater than or equal to 0.12 second) is seen in 11% of elderly men and 5% of elderly women. Aside from age and sex, logistic regression indicates strong associations with concurrent manifestations of coronary heart disease, congestive heart failure, and atrioventricular block, as well as hypertension, left ventricular hypertrophy, and ventricular extrasystoles. Among those subjects free of clinical coronary disease and congestive heart failure, associations between QRS interval and age, sex, atrioventricular block, and ECG left ventricular hypertrophy remain significant by multivariate analysis. Whether people with prolonged QRS intervals need special monitoring or attention cannot be told from these data.
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PMID:Prevalence of intraventricular block in the general population: the Framingham Study. 278 19

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

Three cases of hypertrophic cardiomyopathy (HCM) which presented with different modes of appearance of left ventricular hypertrophy are reported. Case 1: A 24-year-old man had three relatives with HCM. At 13 years of age, he showed no electrocardiographic or echocardiographic abnormalities characteristic of HCM. During the ensuing 11 years, he developed asymmetric septal hypertrophy (ASH) and systolic anterior motion of the mitral valve (SAM), with right bundle branch block and T-wave inversion. Cardiac catheterization confirmed the diagnosis of hypertrophic obstructive cardiomyopathy by demonstrating an intraventricular pressure gradient of 25 mmHg. These observations indicate that this case developed abnormal hypertrophy during adolescence on the basis of genetic predisposition of an autosomal dominant trait. Case 2: A 51-year-old woman had three proven and three possibly affected relatives. At 35 years of age, she had a normal electrocardiogram, although the echocardiogram was not available. Now, 16 years later, she had developed ASH with abnormal Q-waves and was diagnosed as having non-obstructive HCM. These suggest that ASH can be manifested as late as during middle-age, even in those with genetic predisposition. Case 3: A 47-year-old woman was diagnosed as having hypertension and her blood pressure was 190/100 mmHg at 40 years of age, though she had no abnormal electrocardiographic findings and heart murmurs. Now, at 47 years of age, she had developed T-wave inversion, ASH, SAM, and an intraventricular pressure gradient of 50 mmHg. Thus, her ASH appeared during middle-age, and was probably provoked by hypertension, though a complete family survey could not be conducted. These three patients' findings indicate that there may be various modes of appearance of left ventricular hypertrophy in HCM. In the majority of patients with genetic predisposition, abnormal hypertrophy may develop during adolescence as in Case 1. In others, it may develop in middle-age, as it did in Case 2. The disease spectrum of HCM may additionally include those who develop abnormal hypertrophy during middle-age, following provocation by hypertension, as in Case 3.
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PMID:[Hypertrophic cardiomyopathy manifesting different modes of illness: report of three cases]. 342 21

Two hundred consecutive patients undergoing only coronary bypass surgery were studied. Forty-five patients (group A) developed new fascicular conduction blocks and 155 patients (group B) did not. The 45 patients in group A developed the following fascicular conduction blocks: right bundle branch block 47%, right bundle branch block and left anterior hemiblock 8%, right bundle branch block and first-degree atrioventricular block 2%, left anterior hemiblock 11%, left bundle branch block 18%, right bundle branch block-left anterior hemiblock and first-degree atrioventricular block 5%. There were no significant differences in sex, incidence of diabetes, number of grafts performed, ejection fraction (less than 55%), and perioperative infarction. Group A patients were older (p less than 0.01). Hypertension was found frequently in group A (27 vs 45 patients; p less than 0.01) and was present for a mean of 12.4 years in group A and 4.9 years in group B (p less than 0.01). Preoperative use of digitalis was found in 14 (31%) patients in group A and in 18 (12%) patients in group B (p less than 0.01). Twenty-one (47%) patients in group A had significant disease (greater than 70%) of the left main coronary artery as compared to 17 (10.9%) in group B (p less than 0.001). There was no difference in the recurrence of angina or the survival rate at 14 months. In conclusion, the incidence of new fascicular conduction block after bypass surgery is 22.5%. Long-standing hypertension, left main coronary disease, and the preoperative use of digitalis appear to be predisposing factors. New fascicular conduction block does not affect prognosis.
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PMID:Etiology and clinical significance of new fascicular conduction defects following coronary bypass surgery. 348 81

The evolutive characteristics, as well as the qualification criteria, applied to 41 cases of complete right bundle branch block (CRBBB), detected in a presumably healthy population composed of 6,915 male individuals performing civil flying activities (prevalence = to 5.9 per 1,000) were studied. In 17 cases, the CRBBB was detected in the first electrocardiogram (ECG). In 24 cases, the CRBBB appeared after normal ECGs; the CRBBB development did not change the electrical axis in 75%, and in 50% of them an incomplete right bundle branch block (IRBBB) appeared first, suggesting a progressive compromise of the right bundle branch. One case developed arterial hypertension and coronary heart disease, another one mitral valve prolapse, and there were two cases of non-cardiovascular diseases. The CRBBB etiology in asymptomatic individuals is uncertain. The prognosis depends on the underlying disease. Once those etiologies which by themselves imply a future risk are ruled out, they may be waivered for flying activities with periodical ECG controls.
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PMID:Intraventricular conduction disturbances in flying personnel: right bundle branch block. 348 9

Closed-chest trauma in a young man was followed by rupture of a right ventricular papillary muscle and bifascicular block. This produced signs and symptoms of tricuspid regurgitation and recurrent syncope. Treatment by valve replacement and pacemaker implantation was successful. Review of 30 cases of traumatic tricuspid regurgitation reveals that this patient had characteristic findings: adult onset of isolated tricuspid regurgitation, a history of trauma, right bundle branch block, and cardiomegaly without signs of left ventricular failure. In addition, right atrial hypertension of longstanding may produce cyanosis because of right-left shunting through a patent foramen ovale.
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PMID:Chronic tricuspid regurgitation and bifascicular block due to blunt chest trauma. 394 68


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