Evaluation of serial QRS changes during acute inferior myocardial infarction using a QRS scoring system

The evolution of changes in the QRS complex during the initial 3 days after the onset of an initial inferior myocardial infarction (MI) was studied in 82 consecutive patients. Each patient's standard 12-lead electrocardiogram was assigned points (a QRS score) according to the absolute duration of the Q and R waves and the amplitude ratios of R-to-Q and R-to-S waves. This QRS score has been demonstrated to correlate (r = 0.74) with the anatomic extent of single inferior MI. By this system, 43 patients (53% of the study group) had an initial electrocardiogram that registered a score of 0 and developed QRS points only after admission. The QRS scores of 18 additional patients (22% of the study group) changed after admission. Forty-nine score changes were noted on Day 2 and 18 on Day 3. All of these changes resulted in an increased QRS score. Alteration of the QRS complex during initial inferior MI evolves over 2 to 3 days in many patients. There is a distinct pattern to this evolution, which results in sequential increases in a QRS score based upon electrocardiographic indicators of the extent of myocardial necrosis. This QRS scoring system might be applied to evaluate clinically interventions aimed at limiting the extent of necrosis in patients with initial acute inferior MI.     

Comparative rates of resolution of QRS changes after operative and nonoperative acute myocardial infarcts

An independently developed and previously validated QRS scoring system for estimating myocardial infarct size has been used to compare the development and regression of changes associated with myocardial infarcts occurring in 2 different clinical settings. It is known that QRS changes suggesting myocardial infarction occur after coronary artery bypass grafting. This study compares the magnitudes and time courses of these QRS changes in 40 patients with the QRS changes observed in a control group of 46 patients with nonoperative acute myocardial infarcts. Only patients in both groups who had a baseline electrocardiogram (ECG) with no evidence of previous myocardial infarcts, ventricular hypertrophy, or bundle branch block were included. Both groups attained similar peak QRS scores during the acute phase but different rates of resolution of scores were observed. During the subsequent 2 months, regression of QRS changes occurred more rapidly in the perioperative group than in the control group (43 versus 19%). Rates of regression were similar in both groups during the remainder of the follow-up period, attaining total decreases of 62% in the operative group and 37% in the nonoperative group by 18 months. These results could mean either that factors other than acute infarction are responsible for the perioperative QRS changes or that the infarct healing process in the 2 clinical settings are quite different.     

Out-of-hospital management of cardiac arrest by basic emergency medical technicians

The outcome in 126 consecutive patients with nontraumatic out-of-hospital cardiac arrest was analyzed to determine the effectiveness of a standard ambulance system over 22 months. Therapy was limited to basic life support (that is, administration of oxygen by mask, i.v. fluids, closed-chest massage and artificial respiration) by emergency medical technicians in a community in which less than 1% of the population had been trained in cardiopulmonary resuscitation (CPR). Analyses of patient data were performed to determine the relations between survival to hospital admission or discharge and 6 variables; response time, prior CPR, initial rhythm, acute myocardial infarction, initial blood pressure and initial pulse. Of 126 patients, 28 (22%) survived to hospital admission and 11 (9%) to hospital discharge. Two patient subgroups had a higher discharge rate: those with an initial rhythm of ventricular tachycardia or fibrillation (7 of 50, 14%), and those with an initial blood pressure greater than or equal to 90 mm Hg and a pulse rate of greater than 50 beats/min (3 of 6, 50%). For patients in arrest before ambulance arrival, there was no difference in outcome between those who did or those who did not receive prior CPR. Results of this study can be used as a basis for evaluating and comparing interventions directed toward stabilization of patients during the prehospital phase of cardiac arrest.     

Supraventricular tachycardia dependent upon accessory pathways in the absence of ventricular preexcitation

Paroxysmal supraventricular tachycardia is a common disorder of cardiac rhythm, generally thought to be due to reentry within the atrioventrlcular (A-V) node. The possibility that this disorder may be a manifestation of the Wolff-Parkinson-White syndrome should always be considered, but this etiology is usually rejected if the electrocardiogram in sinus rhythm falls to demonstrate a delta wave (i.e., ventricular preexcitatlon). Several recent reports have demonstrated that an accessory A-V pathway may conduct impulses only in the retrograde or ventriculo-atrial direction. Hence, reentrant tachycardia based on a mechanism identical to that observed in patients with classic Wolff-Parkinson-White syndrome may occur, and the electrocardiogram in sinus rhythm fail to show a delta wave. This report describes 11 patients who presented with paroxysmal supraventricular tachycardia without QRS changes in sinus rhythm that suggested the Wolff-Parkinson-White syndrome. Electrophysiologic studies demonstrated that an accessory pathway participated in the mechanism of the tachycardia. Eight of these 11 patients were successfully treated by surgical interruption of either the accessory pathway or the bundle of His. Accessory pathways are not rare among patients with paroxysmal supraventricular tachycardia; and it follows that this variant of the Wolff-ParkinsonWhite syndrome is more common than would be suspected if the Wolff-Parkinson-White syndrome is considered only when delta waves are observed on the electrocardiogram.     

Juxtaglomerular hyperplasia and hyperreninemia in progressive systemic sclerosis complicated acute renal failure

The etiology of renal failure in progressive systemic sclerosis remains unexplained. In this patient with progressive systemic sclerosis rapidly progressive azotemia developed resulting in death. Kidney tissue obtained by percutaneous renal biopsy and later at autopsy revealed striking hyperplasia of the juxtaglomerular apparatus. The plasma renin activity measured by bioassay was extremely high. The clinical and morphologic findings in this patient suggest a possible pathophysiologic role for the renin-angiotensin system in the acute renal decompensation that occasionally occurs in progressive systemic sclerosis.     

Estimating the likelihood of significant coronary artery disease

Among 23 clinical characteristics examined in 3,627 consecutive, symptomatic patients referred for cardiac catheterization between 1969 and 1979, nine were found to be important for estimating the likelihood a patient had significant coronary artery disease. A model using these characteristics accurately estimated the likelihood of disease when applied prospectively to 1,811 patients referred since 1979 and when used to estimate the prevalence of disease in subgroups reported in the literature. Since accurate estimates of the likelihood of significant disease that are based on clinical characteristics are reproducible, they should be used in interpreting the results of additional noninvasive tests and in quantitating the added diagnostic value.     

Deficiency of the fifth component of complement in human subjects. Clinical, genetic and immunologic studies in a large kindred.

The discovery of a large kindred with a heritable deficiency of the fifth component of complement (C5) has permitted the accumulation of new clinical, genetic and immunologic data concerning the role of C5 in human subjects. The proband, who has had nine episodes of disseminated gonococcal infection, has a hemolytic C5 level of approximately 0.5 per cent of normal. No C5 protein was detectable, but low levels of functional C5 activity could be found using a sensitive bactericidal assay. The proband's twin as well as another sister also had extremely low levels of hemolytic C5(approximately 0.5 per cent normal), but both these subjects have been healthy. Hemolytic complement and bacteriolytic activity could be restored by the addition of purified C5. No chemotactic activity for polymorphonuclear leukocytes could be generated in the C5-deficient serums upon activation of either the classic or alternative pathways, again demonstrating the importance of C5 in human subjects for the production of chemotactic factors. The chemotactic responsiveness of the patients' polymorphonuclear leukocytes and monocytes to preformed chemotactic factors was not depressed. Twenty-two of 32 other family members from three generations had depressed whole hemolytic complement levels. In 19 of 30 family members, levels of hemolytic C5 ranged from 13 to 64 per cent of normal. No linkage for C5 deficiency and the A or B loci of the major histocompatibility complex could be found. These data suggest an autosomal codominant mode of inheritance of C5 deficiency. Deficiency of C5 is compatible with good health, but it can be associated with repeated disseminated gonococcal infection.     

Factors affecting sensitivity and specificity of exercise electrocardiography: Multivariable analysis

Unlike the predictive value of a diagnostic test, which depends on the prevalence of disease in the population tested, its sensitivity and specificity have been assumed to be constants. This assumption was examined in patients who had both exercise electrocardiography and cardiac catheterization. The effects on sensitivity of factors from clinical history, catheterization, and exercise performance were defined by multivariable logistic regression analysis in 1,401 patients with coronary disease; effects on specificity were defined by a similar analysis in 868 patients without coronary disease. Five factors had significant, independent effects on exercise electrocardiographic sensitivity: maximal exercise heart rate, number of diseased coronary arteries, type of angina, and the patient's age and sex. Only maximal exercise heart rate had a significant, independent effect on exercise electrocardiographic specificity. Thus, the sensitivity and specificity of exercise electrocardiography vary with clinical history, extent of disease, and treadmill performance; the sensitivity and specificity of other diagnostic tests may also vary.     

Functional properties of accessory atrioventricular pathways in Wolff-Parkinson-White syndrome: Clinical implications

The Wolff-Parkinson-White syndrome is an uncommon cardiac disorder due to the presence of an accessory atrioventricular pathway resulting in ventricular pre-excitation and supraventricular tachycardias. The recognition of the Wolff-Parkinson-White syndrome is important because of the potential for the development of extremely rapid ventricular rates during atrial fibrillation that may lead to ventricular fibrillation and sudden death. The diagnosis of the Wolff-Parkinson-White syndrome is obvious when classic delta waves and short P-R intervals are present, but the electrocardiographic manifestations of the syndrome may be subtle and vary considerably from patient to patient. Certain commonly used antiarrhythmic medications may be useful for the treatment of reciprocating tachycardia in these patients and yet prove to be ineffective—or even deleterious—in preventing excessively rapid conduction to the ventricles during atrial fibrillation. An appreciation of the functional properties of the accessory pathways in the Wolff-Parkinson-White syndrome and how they are affected by pharmacologic agents should result in improved recognition of this entity and more effective medical management of patients with a risk of sudden death.     

Group B streptococcal arthritis in adults

Group B beta-hemolytic streptococci (Streptococcus agalactiae) have been a rare cause of septic arthritis in adults. Only 18 cases have been cited in the literature, eight of which were described since 1976. Two additional cases occurring in the last year are described herein. Like other infections caused by group B streptococci, the incidence of septic arthritis due to these organisms appears to be increasing. A review of these 20 cases revealed a history of prior arthritis or trauma to the involved joints in 30 percent, and an additional 30 percent occurred in potentially immunocompromised hosts. Four of the patients had probable oligoarticular group B streptococcal arthritis. Although most deaths occurred in the pre-penicillin era, early recognition and treatment are essential to prevent joint destruction.     

Normocalcemic pseudohypoparathyroidism. Association with normal vitamin D3 metabolism.

Pseudohypoparathyroidism is a pleiotropic genetic disease of variable expression. Recent observations suggest that the hypocalcemia and bone refractoriness to parathyroid hormone, typical of this disorder, are secondary to impaired production of 1,25-dihydroxycholecalciferol. An incomplete variant of this disease entity, marked by normocalcemia, has been recognized. In this study we investigated whether variable expression of the apparent defect in vitamin D₃ metabolism underlies the normocalcemic variant of this disease. An 18 year old woman with normocalcemic pseudohypoparathyroidism was studied. The diagnosis was confirmed by an absent phosphaturic and urinary cyclic adenosine monophosphate (AMP) response to parathyroid hormone (PTH). Despite this diagnosis the normal serum calcium concentration suggested the presence of normal bone responsiveness. Moreover, the presence of a calcemie response to PTH and a normal serum PTH concentration was consistent with normal PTH bone dynamics. Measurement of 1,25-dihydroxycholecalciferol yielded a normal value in contrast to the decreased concentration of this active vitamin D₃ metabolite present in patients with “hypocalcemic” pseudohypoparathyroidism. The association of a normal serum calcium level, normal bone responsiveness to PTH and normal vitamin D₃ metabolism, in our patient, is consistent with the hypothesis that a decreased serum concentration of 1,25-dihydroxycholecalciferol may be causal of the hypocalcemia in pseudohypoparathyroidism. In addition, these data suggest that variable expression of the apparent defect in vitamin D₃ metabolism may underlie the normocalcemic variant of this disorder.     

Kallman's syndrome with associated cardiovascular and intracranial anomalies

A patient with Kallman's syndrome was found to have an atrial septal defect, mitral valve prolapse, and a large intracranial cyst. None of these anomalies has been previously reported in association with Kallman's syndrome, and all have diagnostic and prognostic importance.     

Pulmonary arterial diastolic pressure in acute myocardial infarction

Pulmonary arterial diastolic pressure has been shown to be a reliable estimate of left ventricular filling pressure. In 91 patients with acute myocardial infarction, the Swan-Ganz flow-directed catheter was used to measure pulmonary arterial diastolic pressure, which was correlated with clinical and radiographic estimates of left ventricular failure. The physical findings of a third sound gallop and rales were significantly correlated with the level of pulmonary arterial diastolic pressure. In the absence of either a third sound gallop or rales, the pulmonary arterial diastolic pressure was found to be increased in 47 percent of the patients. The presence of rales was a less sensitive determinant of left ventricular dysfunction than a third sound gallop alone or in association with rales. Radiographic findings of increasing pulmonary congestion were significantly correlated with the level of pulmonary arterial diastolic pressure. In the absence of radiographic pulmonary congestion, 24 percent of patients had abnormal pulmonary arterial diastolic pressure. We conclude that measurement of pulmonary arterial diastolic pressure increases the objectivity of the clinical evaluation in patients with acute myocardial infarction.     

Membranoproliferative glomerulonephritis: Progression from the pure form to the crescentic form with recurrence after transplantation

Described are the clinical course and renal morphologic findings in a patient with membranoproliferative glomerulonephritis. Initially, the patient had a pure form of membranoproliferative glomerulonephritis but after a 3 year course, it became crescentic. After a renal allograft was performed, membranoproliferative glomerulonephritis recurred within 1 month in a pure form and subsequently developed into the crescentic form. This change occurred in the host kidney as well as in the allograft immediately after immunosuppressive and steroid therapy was discontinued.     

Evaluation of recurrent glomerulonephritis in kidney allografts

The clinical records and biopsy and nephrectomy specimens from 320 patients treated at the Duke University Medical Center between 1965 and 1977 were examined to determine the type and incidence of recurrent glomerulonephritis in the allograft. The diagnosis of recurrent disease required that the histopathologic features of the transplanted kidney resemble those of the diseased native kidney by immunofluorescence and light and electron microscopy. Of 204 patients with tissue available for evaluation from both the native and the transplanted kidney, 117 had some form of chronic glomerulonephritis. Of the 117, there were 61 whose disease could be subclassified further. Idiopathic membranous glomerulonephritis was documented in seven patients, IgA nephropathy in five, focal glomerular sclerosis in 20, type 1 membranoproliferative glomerulonephritis in 16, type 2 membranoproliferative glomerulonephritis in two, proliferative glomerulonephritis in five, crescentic proliferative glomerulonephritis in four and anti-glomerular basement membrane disease in two. In this group of 61, there were 19 patients with 21 allografts in which there was evidence of recurrent glomerulonephritis including four each with idiopathic membranous glomerulonephritis and focal glomerular sclerosis, seven with type 1 membranoproliferative glomerulonephritis, two each with type 2 membranoproliferative glomerulonephritis and anti-glomerular basement membrane disease and one each with IgA nephropathy and crescentic proliferative glomerulonephritis. There were 104 living related donor kidneys grafted into patients with chronic glomerulonephritis, and 78 had tissue available for evaluation. In this group, 15 patients had 16 grafts with recurrent glomerulonephritis. There were 55 cadaveric donor kidneys transplanted into patients with chronic glomerulonephritis, and 39 had tissue available for evaluation. In this group, there were five examples of recurrent glomerulonephritis. Thus, recurrent glomerulonephritis can occur in a variety of histologic subtypes, and in this study population, recurrent glomerulonephritis was more common in allografts from living related donors.     

Ultrasound diagnosis of pseudoaneurysm and contiguous ventricular septal defect complicating inferior myocardial infarction

Two patients with recent inferior myocardial infarction were found by two-dimensional and Doppler echocardiography to have both an inferior wall pseudoaneurysm and a contiguous rupture of the posterior ventricular septum. The pseudoaneurysm was not suspected clinically in either patient. In one patient, a complex or dissecting septal rupture was visualized in detail. To our knowledge, the combined defect has not previously been diagnosed during life by noninvasive methods.     

Prognostic implications of ventricular arrhythmias during 24 hour ambulatory monitoring in patients undergoing cardiac catheterization for coronary artery disease

The prognostic importance of ventricular arrhythmias detected during 24 hour ambulatory monitoring was evaluated in 395 patients with and 260 patients without significant coronary artery disease. Ventricular arrhythmias were found to be strongly related to abnormal left ventricular function. A modification of the Lown grading system (ventricular arrhythmia score) was the most useful scheme for classifying ventricular arrhythmias according to prognostic importance. When only noninvasive characteristics were considered, the score contributed independent prognostic information, and the complexity of ventricular arrhythmias as measured by this score was inversely related to survival. However, when invasive measurements were included, the ventricular arrhythmia score did not contribute independent prognostic information. Furthermore, ejection fraction was more useful than the ventricular arrhythmia score in identifying patients at high risk of sudden death.