Manifestation Of Heart Disease Research Articles

Risks of untreated hypertension. A discussion.

There is a strong and graded association between blood pressure and the incidence of major coronary heart disease manifestations, congestive heart failure, stroke, and total mortality. The risk of any of these manifestations is also modified by other risk factors. Tobacco smoking affects the risk for all of the previously mentioned end points. Generally, lipid disturbances are only important predictors of coronary heart disease and total mortality. Several facts indicate that elevated blood pressure is causally related to the end points. There are, however, positive relations between blood pressure levels and heart rate, serum cholesterol level, body mass index, and, according to some studies, glucose intolerance. Some more basic abnormality may be responsible for the blood pressure increase and the increases in these other factors. Hypothetically, this abnormality may be more fundamentally related to some of the end points than is hypertension itself. If that is the case, then the type of antihypertensive treatment may be of decisive importance. Different end points may be affected differently by antihypertensive drugs, a factor that may be essential in the choice of drug treatment. Proper management of other risk factors is also essential in the prevention of cardiovascular disease.

Role of transesophageal pacing in evaluation of palpitations in children and adolescents

Transesophageal atrial pacing was used to evaluate the cause of palpitations in 28 patients ages 3 to 18 years (mean 11). Palpitations were defined as the sustained (seconds to minutes) sensation of rapid heart beating. Each patient had had >2 episodes of palpitations. No patient had other evidence of heart disease. Standard electrocardiogram was normal (23 of 28 patients), demonstrated ventricular preexcitation (3 of 28 patients) or demonstrated short PR interval (2 of 28 patients). In selected patients, ambulatory monitoring (11 patients) or exercise testing (3 patients) was performed but failed to demonstrate a cause of palpitations. In an effort to initiate tachycardia, a similar transesophageal atrial pacing protocol was performed in each patient. The protocol consisted of: (1) single extrastimuli at progressively closer intervals during sinus rhythm and after an 8-beat pacing train at ≥1 cycle lengths and (2) incremental atrial pacing to the point of second-degree atrioventricular block. If this pacing regimen failed to initiate tachycardia, it was repeated during isoproterenol infusion (0.02, 0.05 and 0.1 μg/kg/min) and then following intravenous atropine (0.04 mg/kg) administration. During the study, tachycardia was initiated in 20 of 28 patients (71%) (14 of 15 patients >10 years, 6 of 13 patients ≤10 years; p < 0.01, Fisher's exact test). Electrophysiologic characteristics of induced tachycardia suggested reentry within the atrioventricular node (8 of 20 patients) or orthodromic reciprocating tachycardia (12 of 20 patients). In 3 of 12 patients with orthodromic reciprocating tachycardia, a transition to atrial fibrillation was observed. In 8 patients without inducible tachycardia, undocumented symptoms continued in 3, symptoms ceased in 4 and ventricular tachycardia was subsequently documented in 1 patient. Transesophageal atrial pacing is useful for investigation of palpitations in young patients without other manifestations of heart disease, especially in patients >10 years of age since electrocardiogram documentation of tachycardia is obtained in most patients studied.

Left bundle branch block: A continuously evolving concept

Eppinger and Rothberger in 1909 and 1910 first acknowledged the importance of the conduction system, yet a confusion of the pattern of left bundle branch block with right bundle branch block resulted which persisted for 25 years. In left bundle branch block, right ventricular endocardial activation begins before, and is often completed before, initiation of left ventricular endocardial activation. Most likely, right to left septal activation then follows, resulting in left ventricular endocardial activation. Although it is hazardous to make definitive diagnoses of infarction in the presence of left bundle branch block, clues do exist. Benign left bundle branch block is rare; usually disease becomes manifest. Electrocardiographic criteria of hypertrophy are not as helpful in older patients with chronic left bundle branch block (mainly because of the very high incidence of left ventricular hypertrophy) as in younger patients with block of nonatherosclerotic origin. Left bundle branch block is often associated with other abnormalities of the conduction system. Fascicular blocks may mask or mimic myocardial infarction. Left posterior fascicular block is most often an indicator of left ventricular myocardial deficit if right ventricular enlargement is eliminated. Mortality is higher in patients with associated left axis deviation than in those with a normal axis, although the incidence of progression of atrioventricular (AV) block is low. In symptomatic patients with prolonged His to ventricular intervals, the incidence of progression of AV block is higher (12%). Preexisting left bundle branch block in the absence of clinical evidence of heart disease is rare, yet carries with it a slightly increased mortality. Newly acquired left bundle branch block carries a 10-fold increase in mortality; the incidence of sudden death as the first manifestation of heart disease is increased 10-fold.

Clinical profiles of cerebrovascular disorders in a population-based patient sample

Clinical features of different types of stroke were investigated in a sample of 409 patients representative of all cases admitted for acute stroke, except subarachnoidal hemorrhages, within a well defined population. A specific cerebrovascular diagnosis was obtained by detailed clinical investigation, including CT scan. In people > 50 years old, men/women risk for stroke was estimated to be 1.40:1. The risk was higher in men up to the age of 80; above this age similar risk for the two genders was observed. Eleven per cent had intracerebral hemorrhage, 13% TIA, 51% non-embolic and 25% embolic brain infarction. In all diagnostic categories there were similar proportions of patients who had a history of hypertension and previous stroke, neither did hemoglobin and hematocrit levels differ between the different stroke disorders. TIA preceded intracerebral hemorrhage in 11% and brain infarction in 15–20%. As opposed to patients with ischemic lesions, subjects with intracerebral hemorrhage had higher systolic blood pressure levels and more severe symptoms on admission to hospital. Ischemic stroke was associated with male predominance, different ischemic manifestations of heart diseases and diabetes.

ELECTRICAL SAFETY OF THE HEART

Outline of Problem: Sudden unexpected cardiac death is one of the most important Public Health problems in the affluent societies. The apparent occurence is about 150, 000 per 100 million population/year. In about one-half of the victims, sudden cardiac death is the first manifestation of heart disease (usually coronary) . In the vast majority of persons with good ventricular function, the mechanism is ventricular fibrillation (VF) . In some victims with severely impaired ventricular function, additional (numerically less important) mechanisms include: ventricular tachycardia (VT), cardiac standstill, and electro-mechanical dissociation.Ventricular premature complexes are nearly ubiquitous and increase in frequency and“complexity”exponentially with age, and also with increasing severity of heart disease. I will examine the relation between these arrhythmias and sudden cardiac death, and will propose that the simple and“complex”ventricular arrhythmias, including nonsustained VT are not precursors of either sustained VT, or VF. Sustained VT is usually a marker of severely impaired ventricular function i.e. a breakdown of electrical safety mechanisms protecting the heart whereas VF is an electrical accident caused usually by severe myocardial ischemia, and sometimes by marked increase in the dispersion of ventricular repolarization (frequently associated with long QT interval) .Hypothesis: The apparent paradox of nearly perfect electrical safety in the presence of variety of ubiquitous ventricular arrhythmias, and the occurrence of fatal electrical accidents unrelated to these arrhythmias may be better understood if we examine the electrophysiologic mechanisms of experimental and clinical accidents encountered in practice and in the laboratory. Extrapolating from these accidents, the following safety factors appear to protect the healthy heart from electrical accidents; 1) Hierarchy of escape pacemakers, 2) Impulse delay in the A-V node + long refractoriness of the conducting system, 3) High (negative) stable resting membrane potential, 4) Fast and uniform ventricular conduction, 5) Long absolute and short relative refractory period of ventricular myocardium, 6) Small dispersion of ventricular repolarization, 7) Uniform ventricular polarization, and 8) Large safety factor inherent in a small ratio of the duration of impulse propagation to the duration of refractoriness in the ventricle.The following examples, and causes of the safety breakdown will be briefly presented: 1) Cardiac standstill—failure of escape pacemakers, 2) Ventricular flutter during atrial flutter and conduction through the Kent bundle—loss of normal protection afforded by the A-V nodal function, 3) Ventricular fibrillation in hypokalemia—diastolic depolarization as well as short absolute and long relative refractory period of the ventricular myocardium, 4) Electrocution—nonunif orm polarization, 5) Induced ventricular tachyarrhythmia by extrastimulation—shortening the refractory period and slowing conduction, 6) Ventricular tachyarrhythmia due to digitalis toxicity—induction of diastolic depolarization and afterdepolarizations, 7) Torsade de pointe in congenital long QT syndrome—increased dispersion of ventricular repolarization, 8) Primary VF in the presence of myocardial ischemia—nonunif orm polarization resulting in slow and nonunif orm conduction.Conclusions: The heart is remarkably well protected from electric accidents. They occur under unusual circumstances, representing mainly the consequences of modern lifestyle, and occasional congenital defects.

Electrocardiographic Abnormalities in Apparently Healthy Men and the Risk of Sudden Death

Identification of individuals at increased risk of sudden cardiac death is an important but difficult problem, especially in persons without clinically apparent heart disease. The ability of the electrocardiogram (ECG) to predict sudden death was determined in a study of 3983 men who were 30.8 years of age (mean) at entry and who had been followed with regular examinations, including ECGs. During the 30-year observation period, 70 cases of sudden death occurred in men without previous clinical manifestations of heart disease. Electrocardiographic abnormalities were detected before sudden death in 71.4% of cases. The abnormalities were, in decreasing order of frequency, ST segment and T-wave abnormalities, ventricular extrasystoles, left ventricular hypertrophy, complete left bundle branch block, and pronounced left axis deviation. When these electrocardiographic findings in men without clinical manifestations of heart disease were related prospectively to the incidence of sudden death, ST segment and T-wave abnormalities, ventricular extra-systoles, left ventricular hypertrophy and complete left bundle branch block were significant predictors of sudden death, while left axis deviation and right bundle branch block were not significant predictors of sudden death. Increased severity of primary T-wave abnormalities and the association of ST segment and T-wave abnormalities with increased QRS voltage further increased the sudden death risk. The combination of ventricular extrasystoles with either ST-T abnormalities or left ventricular hypertrophy considerably increased the risk of sudden death. Thus, these data indicate that electrocardiographic abnormalities detected on routine examination in men without clinical evidence of heart disease identify men at an increased risk of sudden death.

Results of endomyocardial biopsy in patients with spontaneous ventricular tachycardia but without apparent structural heart disease.

To evaluate possible occult myocardial disease in 18 patients whose only major manifestation of heart disease was spontaneous ventricular tachycardia or fibrillation, right ventricular endomyocardial biopsies were performed. None of the patients had symptoms of ischemic or congestive heart disease, and at catheterization none had significant lesions of the coronary arteries or regional wall motion abnormalities of the left ventricle. The mean left ventricular ejection fraction (65 +/- 7%), mean right ventricular ejection fraction (55 +/- 9%), mean cardiac index (3.0 +/- 0.5 1/min/m2), mean right atrial pressure, mean pulmonary capillary wedge pressure, and mean pulmonary artery systolic pressure were normal. However, right ventricular endomyocardial biopsy specimens were abnormal in 16 of 18 (89%) patients: nine (50%) had changes of a significant, although nonspecific, cardiomyopathy with myocellular hypertrophy, interstitial and perivascular fibrosis, and vascular sclerosis; three (17%) had subacute inflammatory myocarditis; two (11%) had diffuse abnormalities of the intramyocardial arteries; and two (11%) had pathologic changes consistent with arrhythmogenic right ventricular dysplasia. In the two (11%) patients with normal biopsy specimens, one had Wolff-Parkinson-White syndrome and the other had mitral valve prolapse. Although histologic abnormalities were found in 89% of these patients, performance of right ventricular endomyocardial biopsies in this group of patients should be considered a research procedure. We conclude that the majority of patients who have serious ventricular arrhythmias but no apparent structural cardiac abnormalities have abnormal right ventricular biopsy specimens and that the arrhythmias may be the first manifestation of a variety of primary myocardial abnormalities.

The electrocardiogram in apparently healthy men and the risk of sudden death.

The purpose of this study was to determine whether electrocardiographic abnormalities detected on a routine examination in men without clinical evidence of heart disease predicted sudden death in the absence of pre-existing clinical manifestations of heart disease. The Manitoba study consists of a cohort of 3983 men with a mean age at entry of 30.8 years who have been followed with regular examinations including electrocardiograms since 1948. During the 30 year observation period, 70 cases of sudden death have occurred in men without previous clinical manifestations of heart disease. The prevalence of electrocardiographic abnormalities before sudden death was 71.4% (50/70). The frequency of abnormalities was 31.4% (22) major ST segment and T wave abnormalities, 15.7/ (11) ventricular extrasystoles, 12.9% (nine) left ventricular hypertrophy (voltage criteria), 7.1% (five) complete left bundle-branch block, and 5.7% (four) pronounced left axis deviation. When these electrocardiographic findings in men without clinical manifestations of heart disease were related prospectively to incidence of sudden death each one except pronounced left axis deviation was a significant predictor of sudden death. Two of the variables were examined in more detail. Increased severity of primary T wave abnormalities and the association of ST segment and T wave abnormalities with increased QRS voltage further increased sudden death risk. The combination of ventricular extrasystoles with either ST-T abnormalities or left ventricular hypertrophy much increased the risk of sudden death. Thus these data indicate that electrocardiographic abnormalities detected on routine examination in men without clinical evidence of heart disease are significantly related to the occurrence of sudden death.

Natural history of left bundle-branch block.

The purpose of this study was to examine factors associated with the development of complete left bundle-branch block and the prognosis in a group of people not in hospital, who had no clinical evidence of ischaemic or valvular heart disease. Twenty-nine cases of left bundle-branch block without clinical evidence of ischaemic heart disease were noted in the Manitoba cohort of 3983 men under observation since 1948. The most frequent electrocardiographic finding before development of left bundle-branch block was a normal electrocardiogram; left ventricular hypertrophy though infrequent, was the only abnormality significantly more common than in the rest of the group. The development of left bundle-branch block was associated with distinct leftward shift of the frontal plane mean QRS axis. The most frequent clinical cardiovascular event observed after development of the block was sudden death without previous clinical evidence of ischaemic heart disease. The five-year incidence of sudden death as the first manifestation of heart disease was 10 times greater in men with left bundle-branch block than in those without it.

Treatment of sinoatrial syndrome with permanent cardiac pacing in 90 patients.

Out of a pacemaker population of 392 patients, 90 (23%) have been found to have sinoatrial syndrome. Their ages ranged from 22 to 86 years, and averaged 66 for men and 70 for women. The male-to-female ratio was 1:1.6. Before pacemaker implantation, syncopal attacks had occurred in 54%, dizziness without syncope in 31% and tachyarrhythmias in 57%. Atrial or paroxysmal supraventricular tachycardia had been recorded in 33%, atrial fibrillation or flutter in 28%, and ventricular tachycardia in 11%. First and/or second degree AV block was found in 36%. Coronary heart disease was present in 61% and 20% had had myocardial infarction. Cardiomyopathy and previous carditis were other associated heart diseases. Sinoatrial syndrome was the only manifestation of heart disease in 20%. Follow-up time after pacemaker implantation ranged from 3 months to 7 years, mean 23 months. Syncopal attacks were stopped in 48 of 49 patients, dizziness was relieved in all 28 patients and tachyarrhythmias were controlled by combined drug treatment in 43 of 51 patients. Nineteen patients died during the follow-up, most of them of cerebrovascular events or myocardial infarction. Associated coronary heart disease was especially frequent in this group. The death of one patient was caused by a run-away pacemaker. Other pacing failures were due to electrode movement or premature battery exhaustion. There was no mortality associated with pacemaker implantations or replacements. These results strongly support the view that pacemaker treatment most effectively controls symptoms of sinoatrial syndrome when drug treatment fails.

Familial right bundle-branch block, left axis deviation, complete heart block, and early death. A heritable disorder of cardiac conduction.

A patient with right bundle-branch block and left axis deviation who later developed complete heart block had a family history suggestive of familial bundle-branch disease and heart block. Investigation of 59 members in four generations of the family showed 26 with abnormal electrocardiograms and 6 with a history of heart block. Seven have right bundle-branch block and left axis deviation; seven have right bundle-branch block, left axis deviation, and intermittent complete heart block. All affected members have conduction abnormalities as the only manifestation of heart disease. The genetic defect appears to be transmitted as an autosomal dominant trait with varying expressivity. This conduction abnormality, not recognized as a heritable disorder, raises questions about the development of the ischemic or degenerative processes thought important in this disease. Additional family studies of individuals with conduction system disease are needed.

Serologic evidence of a sporadic outbreak in Illinois of infection by Chlamydia (psittacosis-LGV agent) in patients with primary myocardial disease and respiratory disease

Northern Illinois experienced an outbreak of chlamydial infection in 1963, 1964, and 1965, as reflected by an increase in the number of patients showing antibody to this group of agents during the period. Among these individuals, a disproportionately large number with PMD showed serologic activity against Chlamydia. This suggests that there was something distinctive about the response of the PMD patients in the face of this outbreak. The clinical manifestations of heart disease in PMD patients were similar regardless of their serologic status, i.e., whether or not they had antibody of Chlamydia. Specific serum reactivity to Chlamydia was verified by: (1) use of multiple chlamydial antigens, (2) application of both complement-fixation and RIP test systems, and (3) absence of reactivity to uninfected egg tissue or to egg tissue infected with Newcastle disease virus. Reactivity to Chlamydia persisted in our PMD population for periods of months to more than five years. While the evidence cited in this paper linking chlamydial agent to the PMD is inferential and no direct evidence of chlamydial infection was found in the tissue of 12 hearts examined, epidemiologic considerations strongly suggest an etiologic relationship.

An Epidemiologic Study of First Degree Atrioventricular Block in Tecumseh, Michigan

PR intervals of 0.22 sec or longer were detected in the electrocardiograms of 95 of 4,678 participants past 20 years of age in the Tecumseh Community Health Study. The prevalence rates were similar in men and women and remained low through the sixth decade, but increased sharply in succeeding decades. Nineteen of the 95 persons had some other manifestation of heart disease and there was a significant association between delayed atrioventricular conduction and angina pectoris or asymptomatic T wave inversion in participants past 60 years of age. Most of the cardiac abnormalities were found among older individuals. Atrioventricular block was more constant on second examination in this group and may have been due in part to sclerosis of the left side of the cardiac skeleton, as well as specific etiologic types of heart disease. Among younger and apparently healthy participants the PR interval usually shortened on repeat examination, frequently to less than 0.22 sec. There was no excess incidence of cardiovascular disease or mortality among the persons with long PR intervals during a mean period of observation of four years. Delay in atrioventricular conduction by itself appears to be a benign condition with no unfavorable prognostic significance. It is probably a transient finding among many members of the population.

Cardiovascular findings in patients with sickle cell anemia

T HIS study was undertaken to reveal the following aspects in patients with sickle cell anemia with or without clinical manifestation of heart disease: (1) the incidence of electrocardiographic abnormalities; (2) radiological evaluation of the chest for cardiomegaly and pulmonary vascular markings ; (3) auscultatory and phonocardiographic findings; and (4) autopsies from reports of 9 patients and the cause of death in 7 patients without autopsy.

Cholesterol and phospholipid content of human β-lipoprotein in different lipemic states and following myocardial infarction

Summary The heparin-phenol precipitation technique of Scanu, Lewis and Page has been found to provide a simple, reliable and reproducible method for the isolation of β-lipoprotein from serum. The total cholesterol/phospholipid ratio of β-lipoproteins (β-C/P ratio) isolated by this technique does not change with age in subjects free from clinical manifestations of heart disease. The β-C/P ratio is slightly elevated in hypercholesterolemic males, and slightly lowered in hypercholesterolemic females, compared with the pooled normal value. The ratio is depressed in patients with thyreotoxicosis, but the value of the ratio in patients with hypothyreosis does not differ from the normal value. Linoleic acid (up to 40 g daily) in the diet does not influence the β-C/P ratio appreciably. Estrogen in the form of dioxydiethylstilbestrol (15 mg daily) depresses the ratio significantly. Only a few hours and on the 2nd day after an acute myocardial infarction the β-C/P ratio is significantly elevated above the normal value. It drops to a level slightly lower than the normal mean in the 3rd week. Re-examination of survivors of acute myocardial infarction in the 3rd month and after the 8th month from the occurrence revealed a significantly depressed β-C/P ratio in the last group, although the absolute amount of β-lipoprotein was much increased. The combined administration of estrogen and androgen effects a significant depression of the β-C/P ratio due to a sharp increase in β-phospholipid. This change is less marked when methyl testosterone is given alone. These changes ara attributed to the appearance, during the abnormal lipemic states described, of β-lipoproteins differing in composition from those given in the literature for various β-lipoprotein classes isolated from normal sera.

The management of paroxysmal atrial fibrillation

Summary If paroxysmal atrial fibrillation is a lone affair, adequate reassurance, explaining that it has a nuisance value and need not be a manifestation of heart disease, is a first need. If the paroxysms are brief and infrequent, such reassurance suffices. Should the paroxysms be prolonged and frequent, digitalization to ensure a slower heart rate and freedom from palpitation is the therapy of choice. The finding of paroxysmal atrial fibrillation may call attention to underlying disease, which in some forms like alcoholism or thyroid toxemia may prove amenable to treatment.

Cardiac involvement in malignant lymphoma.

ALTHOUGH k cases of malignant lymphoma, corresponding clinical manifestations are uncommon and when they do occur usually give rise to considerable diagnostic difficulty. The nature of the diagnostic problem varies with the stage in the development of the lymphoma at which the cardiac symptoms appear. In the rare cases in which the early or presenting symptoms are those of heart disease, the correct diagnosis has seldom been made before autopsy. When a patient known to have a malignant lymphoma complains of cardiac symptoms, the neoplastic origin of these symptoms may be recognized, but in older patients they may be attributed to coronary artery disease. In the terminal stages, anemia and obstructive symptoms and signs often produce a picture closely resembling congestive cardiac failure and the presence of cardiac involvement may be overlooked. The clinical manifestations of heart disease of lymphomatous origin are discussed in this report, and the nature of

RHYTHMIC PROPERTY OF THE HUMAN HEART

The heart is a contractile organ, but it possesses important properties aside from that of contractility. The functions of rhythmicity, conductivity and irritability are also of fundamental importance in cardiac physiology. The clinician's attention is focused mainly on the contractile function of the heart, since the usual methods of examination, palpation of the apical impulse, auscultation of cardiac sounds and inspection of the heart by the fluoroscope, are means by which this property of the heart may be investigated. Furthermore, impairment of contractile efficiency is the basis for the most frequent manifestation of heart disease, congestive heart failure. Rhythmicity is the property of stimulus formation, and since the heart is an automatic organ producing its own stimulus, it is obvious that this function is essential in the normal physiologic processes of the heart. If the rhythmic function is so reduced that no stimulus is produced, there is a sudden cessation

Gastro-intestinal manifestations of heart disease

1. Gastro-intestinal manifestations were noted in 10% of cardiac patients. 2. Pain, distress, or fullness in the epigastric region, over the entire abdomen, or in the right upper quadrant were the most common complaints and occurred either previous to or at the same time as the important cardiac symptoms. 3. Early gastro-intestinal manifestations of heart disease were belching, obstipation, and flatulence, but they were far less frequent in occurrence. 4. All of the gastro-intestinal manifestations were usually unrelenting in character and persisted until the cardiac condition was relieved. 5. Combined gastro-intestinal and heart disease may occur but it is uncommon; only three patients in this series had both conditions present at the same time.

Auricular fibrillation as the only manifestation of heart disease

Ten patients are reported in whom auricular fibrillation was the only evidence of cardiac disease. The factors usually responsible for this irregularity were excluded. The age ranged from seventeen to thirty-four years, and all except two were under thirty years of age. In seven cases the auricular fibrillation was paroxysmal, while in three it had persisted for periods of two weeks, five months, and two and one-half years respectively. In each of the latter instances sinus rhythm was restored by quinidine. The auricular fibrillation in these three cases would probably have continued had quinidine not been given. The patient who had auricular fibrillation for two and one-half years later came to necropsy, and the heart was regarded as grossly and microscopically normal. In one of our cases the auricular fibrillation was attributed to the removal of cerumen from the external auditory canal, one to exertion, four to alcohol, one to carbon monoxide, one to ether and nitrous oxide anesthesia and two were in attendance at gasoline stations. In the thirty-five cases collected from the literature the auricular fibrillation was attributed to such stimuli as electric shock, diseases within the abdomen, emotion and effort and intoxication by various chemical substances. Abdominal disease and alcohol were the most common exciting agents. In the former group it is believed that a reflex stimulation over the vagus contributed to the production of auricular fibrillation.