Preservation of interventricular septal function in patients having coronary artery bypass grafts without cardiopulmonary bypass

Abnormal interventricular septal motion develops in the majority of patients after cardiac surgery and has been attributed to a variety of causes. This study assesses the role of cardiopulmonary (CP) bypass in the genesis of abnormal septal motion. Twenty-two patients having single coronary artery bypass grafts had septal motion and ejection fraction evaluated preoperatively and postoperatively. The results for 11 patients who had coronary artery bypass grafting (CABG) with CP were compared to those for 11 patients who had grafting without CP bypass. Postoperatively, all 11 patients having bypass grafting with CP bypass had diminution in septal function while 10 of 11 patients having bypass grafting performed without CP bypass had no change or improvement in septal motion (p < 0.0005). Changes in ejection fraction were not statistically significantly different. This study suggests that abnormal septal motion in patients having CABG is related to CP bypass and/or myocardial preservation techniques.     

Effect of cardiac surgery on ventricular septal motion: Assessment by intraoperative echocardiography and cross-sectional two-dimensional echocardiography

Echocardiographic evidence of paradoxical septal motion frequently occurs after cardiac surgery. To assess possible etiologic factors 17 patients were studied preoperatively, intraoperatively, and 7 days after surgery. Preoperative septal motion was normal in 14 and paradoxical in three (two with previous cardiac surgery, one with atrial septal defect [ASD]). Intraoperative septal motion prior to surgical procedure was normal in 16 and paradoxical in one (ASD). Septal motion (excursion and thickening fraction) was normal in all patients prior to chest closure. Echocardiograms of adequate quality were obtained at 7 days post surgery in 15 patients; septal motion was paradoxical in nine (group A) and normal in six (group B). No significant differences were seen between the two groups in ischemic time or in the preoperative to postoperative change in left ventricular (LV) and right ventricular diastolic dimension, shortening fraction, or septal and posterior wall thickening fraction. A significant postoperative decrease in septal excursion was seen in group A but not in group B; significant postoperative increases in posterior wall excursion were seen in both groups. Cross-sectional two-dimensional echocardiograms performed in 20 patients (8 normal, 12 postoperative paradoxical septal motion) were analyzed. In normal controls no significant change was detected in the LV centroid position during systole. In contrast, the 12 postoperative patients showed significant anterior displacement of the LV centroid and right septum during systole. Thus, paradoxical septal motion after cardiac surgery appears to relate to excessive anterior cardiac mobility due to pericardiotomy rather than to myocardial ischemia resulting from cardiopulmonary bypass.     

Ischemic myocardial injury during cardiopulmonary bypass surgery

ECG's and serum levels of SGOT, LDH, and CPK were examined during the immediate postoperative period in 126 patients who had cardiac surgery during cardiopulmonary bypass. None had coronary disease and valve replacement was performed in 97 patients. Miscellaneous procedures not involving the coronary arteries were performed in 29. In surviving patients, ECG signs of acute myocardial infarction appeared in 8 (7 per cent) and changes compatible with acute ischemic injury were seen in 38 (30 per cent). Elevation of SGOT exceeding 90 units occurred in 32 per cent of patients and LDH levels over 900 units occurred in 37 per cent. In patients with ECG evidence of postoperative infarction or ischemia, 70 per cent had abnormal SGOT levels and 70 per cent had abnormal LDH levels. In 40 patients with SGOT levels exceeding 90 units, 80 per cent had ECG evidence of acute infarction or ischemia. In 80 patients without ECG changes, only 10 per cent had SGOT levels exceeding 90 units. CPK levels correlated poorly with ECG evidence of ischemia or infarction. Patients who demonstrated ECG and serum enzyme evidence of ischemic injury or myocardial infarction had longer total perfusion times during surgery (P < 0.001) but no relationship to aortic cross clamp time was observed. ECG evidence of acute myocardial ischemia with elevation of serum enzymes is frequently observed following cardiopulmonary bypass surgery. Serial ECG's and measurements of postoperative serum enzymes provide useful information regarding myocardial injury and the effectiveness of bypass perfusion in protecting the myocardium during cardiopulmonary bypass sugery.     

Relationship between septal perfusion, viability, and motion before and after coronary artery bypass surgery.

The etiology of abnormal interventricular septal motion occurring after open-heart surgery using cardiopulmonary bypass has not been clarified. Intraoperative ischemic septal injury has been proposed as one explanation for this finding. To examine this possibility, resting septal perfusion and viability were studied using rest and redistribution thallium-201 scintigraphy in 16 patients before and after coronary artery bypass surgery. The results were compared with septal motion on preoperative and postoperative resting gated blood pool scans. Preoperatively, septal thallium uptake was normal in 10 of 16 patients, and septal motion was normal in 14 of 16. Postoperatively, septal thallium uptake was normal in 11 of 16 patients, while septal motion was abnormal in all. Thus abnormal postoperative septal motion is usually associated with normal septal perfusion and viability on thallium scans and therefore is not the result of septal ischemic injury in a majority of patients.     

Acknowledgment to reviewers

The interventricular septal wall thickness and motion was studied by echocardiography in 25 normal subjects and 43 patients with various cardiovascular disease proved at cardiac catheterization. The mean septal thickness was 7.2 mm. ± 0.7 S.D. in the normal subjects, 10,1 mm. ± 1.0 S.D. in 11 patients with left ventricular volume overload (P < 0.01), and a mean of 12.2 mm. in two patients with pure pressure overload of the left ventricle. Ten patients with coronary atherosclerotic heart disease (CAHD) had an average septal thickness of 9.2 mm. ± 1.1 S.D. and in five patients with congestive cardiomyopathy (CM) it was 9.1 mm. ± 0.8 S.D., and a mean of 17.8 mm. in four patients with IHSS (P < 0.01). In five patients with mitral stenosis the septal thickness did not differ from normal (mean 7.1 mm. ± 0.9 S.D.). Septal motion was correlated with angiographic ejection fraction, pattern of left ventricular wall motion, and coronary angiography. All patients with left ventricular disease and an abnormal septal motion invariably had significant left ventricular dysfunction at cardiac catheterization, particularly patients with CM or severe CAHD, although a normal septal motion does not exclude severe left ventricular dysfunction and hypokinesis.It is concluded that study of the interventricular septum by echocardiography provides a non-invasive technique with a high specificity but a lower sensitivity for identifying patients with left ventricular dysfunction.     

Global and regional left ventricular response to bicycle exercise in coronary artery disease. Assessment by quantitative radionuclide angiocardiography.

The left ventricular response to bicycle exercise was evaluated in 60 patients with coronary artery disease and in 13 normal control subjects. Left ventricular ejection fraction, mean normalized ejection rate and regional wall motion were determined using first-pass radionuclide angiocardiograms obtained at rest and again during peak graded bicycle exercise. All normal subjects demonstrated improved left ventricular function with exercise. Left ventricular ejection fraction increased significantly from 67 ± 3 per cent (mean ± SE) at rest to 82 ± 4 per cent with exercise (p < 0.001). Similarly, the left ventricular ejection rate increased significantly from 3.47 ± 0.31 sec^?1 to 6.53 ± 0.42 sec^?1(p < 0.001). In contrast, in 44 of 60 patients with coronary artery disease, the ejection fraction or ejection rate either decreased or remained the same with exercise. New or exaggerated regional wall motion abnormalities were detected in 28 of 60 patients with coronary artery disease. Over-all, global or regional evidence of compromised left ventricular reserve was found in 48 of 60 patients with coronary artery disease.The major determinant of an abnormal left ventricular response to exercise was the presence or absence of electrocardiographic evidence of myocardial ischemia. Left ventricular ejection fraction decreased or remained the same with exercise in all patients with coronary artery disease and electrocardiographic ischemia. New regional wall motion abnormalities were detected in 20 of these patients. In this group, the left ventricular ejection fraction decreased from 66 ± 2 per cent at rest to 58 ± 2 per cent with exercise (p < 0.001), whereas the ejection rate was unchanged by exercise (rest 3.33 ± 0.21 sec^?1; exercise 3.34 ± 0.22 sec^?1, p > 0.05). Of the 30 patients with coronary artery disease who exercised to symptom-limiting fatigue without electrocardiographic ischemia, 18 demonstrated compromised left ventricular reserve with exercise. Twelve of the remaining patients with coronary artery disease had normal left ventricular reserve, in eight of whom ventricular function was completely normal both at rest and during exercise. In this group exercised to fatigue, the left ventricular ejection fraction increased from 53 ± 4 per cent at rest to 58 ± 2 per cent with exercise (p < 0.001). The ejection rate also increased from 2.48 ± 0.24 sec^?1 to 3.67 ± 0.39 sec^?1 (p < 0.001). The direction and magnitude of the left ventricular responses to exercise were not affected by long-term oral propranolol administration in 22 patients. Based upon either abnormal exercise left ventricular reserve or abnormal global and regional left ventricular function at rest, the over-all sensitivity of this radionuclide technic for the detection of coronary artery disease was 87 per cent (52 of 60 patients). These data demonstrate that exercise ventricular performance studies provide important physiologic insights into left ventricular functional reserve as well as a sensitive noninvasive approach for the detection of coronary artery disease.     

Diagnostic and prognostic significance of electrocardiographic and CPK isoenzyme changes following coronary bypass surgery: correlation with findings at one year.

The incidence of ECG (14 per cent) indication of acute myocardial infarction complicating coronary artery bypass surgery is documented, corroborating the findings of prior series. An additional 32 per cent of patients had appearance of myocardial specific CPK-MB in serum during the immediate postoperative period. All patients surviving to 1 year following surgery (93 of 103) were asked to return for repeat cardiac catheterization to determine the presence and extent of interim ventricular contraction abnormalities. Sixty-five (70 per cent) of the group returned for evaluation. Preoperative and 1 year postoperative left ventriculograms were compared to determine if new contraction abnormalities would confirm the specificity of perioperative QRS and isoenzyme changes, and if the absence of new abnormalities would confirm their sensitivity. The majority of patients (65 per cent) had new areas of asynergy. However, 73 per cent of these were confined to the apex and thus could have been produced by the vent employed during cardiopulmonary bypass. QRS changes were 100 per cent specific and CPK-MB appearance was 78 per cent specific but they were only 20 and 54 per cent sensitive, respectively. Indeed, 46 per cent of those with new asynergy which was non apical had neither QRS change nor CPK-MB appearance. Thus QRS changes were always--and CPK-MB appearance was usually--associated with new asynergy but, in addition, many patients with no perioperative indication of infarction developed new areas of left ventricular contraction abnormality within the first postoperative year.     

Paradoxical septal motion after cardiac surgery: a review of 3,292 cases

BACKGROUND: Paradoxical septal motion (PSM) is the systolic movement of the interventricular septum toward the right ventricle despite normal thickening. The PSM is a frequent echocardiographic finding after cardiac surgery. Although it is universally recognized, there has been no large-scale study to correlate PSM with the type of surgical procedure. The cause of PSM is unknown; prevailing theories include: (1) operation on the heart alters the degree to which it is restrained by the pericardium and the chest wall and (2) transient ischemia alters septal motion. HYPOTHESIS: The PSM is related to type of surgery and surgical approach. METHODS: Between 1996 and 2002, 3,292 patients underwent a first cardiac operation and had a postoperative echocardiogram; 313 were excluded due to other explanations for PSM (severe tricuspid regurgitation [TR] cardiac pacing), leaving a study group of 2,979 patients. Univariate and multivariate analyses were performed to determine which surgical characteristics were correlated with postoperative PSM. Septal thickening was assessed in a subset. RESULTS: On multivariate analysis, aortic (p = 0.02) and mitral valve surgery (p < 0.001) and longer cardiopulmonary bypass time (p < 0.001) were independently associated with PSM. Coronary artery bypass grafting (CABG) was less likely to cause PSM than non-CABG surgery (p = 0.003) and off-pump coronary artery bypass (OPCAB) caused less PSM than did on-pump CABG. CONCLUSIONS: 1. Valve surgery is more likely to cause PSM than CABG. 2. Among patients with CABG, OPCAB causes less PSM. 3. Cardiopulmonary bypass time is associated with the development of PSM. 4. The cause of PSM is likely to be multifactorial.     

Interventricular septal motion and left ventricular function after coronary bypass surgery: evaluation with echocardiography and radionuclide angiography.

To evaluate interventricular septal motion and left ventricular function after coronary bypass graft surgery, 40 patients were studied early postoperatively and serially for up to 16 months with echocardiography and radionuclide angiography. Early after operation mean left septal excursion decreased significantly from 4.6 +/- 0.4 (standard error) to 0.8 +/- 0.6 mm (P less than 0.001), and left septal motion was abnormal in 23 of the 40 patients. Mean right septal excursion reversed from 2.1 +/- 0.5 to -2.1 +/- 0.5 mm early after operation in the 22 patients in whom these measurements could be made, and 15 patients showed paradoxical right septal excursion. At a mean of 4 months after operation, only 7 of 35 patients followed up had abnormal left septal motion, and mean left septal excursion had returned toward normal (3.6 +/- 0.7 mm); mean right septal excursion remained reversed (--1.1 +/- 0.7 mm), and 6 of the 14 patients followed up had paradoxical motion. In the 22 patients whose wall thickness could be measured, mean septal thickening during systole decreased significantly from 35 +/- 4 to 21 +/- 3 percent early after operation (P less than 0.01). During late follow-up septal thickening returned toward normal (32 +/- 4 percent). Mean normalized posterior wall velocity increased significantly after operation from 0.76 +/- 0.03 to 1.01 +/- 0.05 sec-1 (P less than 0.001), but posterior wall thickening remained unchanged. Left ventricular end-diastolic dimension and the radionuclide-determined left ventricular ejection fraction were unchanged postoperatively. It is concluded that (1) echocardiographically detected abnormal septal movement is frequent early after coronary bypass graft operation; (2) both decreased myocardial contraction in the septum and increased anterior movement of the whole heart contribute to this abnormality; (3) the abnormalities in septal movement decrease during late follow-up in many patients but persist in some patients; and (4) posterior wall function tends to increase early after operation and therefore overall left ventricular function remains normal.     

Systemic hypertension following myocardial revascularization

Systemic hypertension was noted to be particularly frequent in the immediate postoperative period following myocardial revascularization procedures. A sustained increase in diastolic pressure to 100 mm. Hg or more occurred in 29 of 80 preoperatively normotensive patients (36 per cent); of 22 patients who were hypertensive before surgery, 5 (23 per cent) had pressure rises of 30 mm. Hg or more above their preoperative levels. Thus, of 102 patients undergoing aortocoronary bypass or internal mammary artery implant, 34 or one third had a hypertensive episode following surgery. There was no significant difference between the two procedures in the incidence of postoperative hypertension (35.5 per cent and 26.9 per cent, respectively, p > 0.10). In contrast, similar episodes were significantly less common following other types of surgery, occurring in only 4 of 107 patients after major noncardiac operations (p < 0.001) and in 2 out of 38 (5 per cent) following cardiac valve replacement (p < 0.005). This difference was not related to anesthetic agents used, to cardiopulmonary bypass, or to preoperative blood pressure levels.The postoperative rise in pressure was not associated with increase in central venous or left atrial pressures or with signs of hypervolemia or of renal dysfunction. It persisted despite adequate analgesia but was usually controlled by intravenous promazine, although sodium nitroprusside had to be used in a few instances. Its frequency after coronary-arterial surgery, its transient course, and the apparent absence of other causes suggest that this hypertension might be related to some coronary pressor reflexes.     

Prognostic value of echocardiographic evaluation of septal function in acute anteroseptal myocardial infarction.

To determine the clinical usefulness of echocardiography in patients with anteroseptal myocardial infarction, echocardiograms were performed within 24 hours of admission on 40 patients with acute transmural anteroseptal myocardial infarction. Twenty-one patients had normal septal motion and septal systolic thickening, and 19 patients had abnormalities of one or both of these measurements. Of the 21 patients who had normal septal motion and thickening, only five developed congestive heart failure, none developed bundle branch block, and none died. Of the 19 patients with abnormal septal motion and/or thickening, 17 developed congestive heart failure (p less than .001), seven developed bundle branch block (p less than .001), and six died (p less than .001). Therefore, (1) electrocardiographic evidence of septal infarction does not correlate with abnormalities of the portion of septum seen on echocardiogram, and (2) patients with anteroseptal myocardial infarction and abnormalities of the septum on echocardiogram have more complications and a higher in-hospital mortality rate. These patients may have more extensive myocardial infarction predisposing to pump failure and possibly involving the conduction system.     

Sequential postoperative assessment of left ventricular performance with gated cardiac blood pool imaging following aortocoronary bypass surgery

The comparative effects of normothermic intermittent ischemic arrest (IIA) and cardioplegia (C) on left ventricular (LV) performance were assessed by gated cardiac blood pool imaging in 57 patients undergoing aortocoronary bypass surgery. In 34 patients, IIA was employed; 23 patients received C. Patients were studied preoperatively, sequentially in the immediate postoperative period at 30-minute intervals, and at 1 week after the operation. C and IIA groups did not differ in mean (± SEM) age, anginal class, number of diseased vessels, previous myocardial infarction, or preoperative ejection fraction (EF) (50 ± 3% vs 50 ± 2% [p = ns]). Aortic cross clamp time was greater with C than IIA (50 ± 5 minutes vs 28 ± 3 minutes [p = 0.001]). During the six sequential postoperative studies, transient LV dysfunction (≥ 7% decrease in absolute EF) was observed in 10 patients receiving C and in 16 patients receiving IIA. By time of discharge, 24 of 26 patients had returned to preoperative EF. Mean EF at discharge in the cardioplegia group did not differ compared to preoperative EF; in the IIA group, EF increased compared to preoperative EF (50 ± 2% vs 55 ± 2% [p < 0.01]). These data suggest that in patients with normal preoperative LV performance both C and IIA afford satisfactory myocardial preservation during aortocoronary bypass surgery.     

Left ventricular regional wall motion assessment by multigated and end-diastolic, end-systolic gated radipnuclide left ventriculography

The validity and accuracy of three methods of gated cardiac blood pool imaging for the determination of regional wall motion were assessed in 124 patients undergoing contrast left ventriculography. Eighty-four patients had multigated acquisition and display, and 40 patients had end-diastolic, end-systolic gated acquisition and display in both a two frame movie format and on photographs. Both gated cardiac blood pool images and left ventriculograms were reviewed independently by three blinded observers and regional wall motion was qualitatively scored. For scoring purposes, the left ventricular wall was subdivided into anterolateral, apical, inferior, septal, apical-inferior and posterior segments. Segmental motion was graded on a five point grading scale as normal, mildly hypokinetic, moderately to severely hypokinetic, akinetic or dyskinetic. The graded scores for regional wall motion for each of the three observers were averaged and then compared. Regional wall motion scores for the gated blood pool study agreed within ± 1 grade with scores for contrast ventriculography in 338 of 402 segments (84 percent) studied with multigated acquisition and display, in 97 of 117 segments (83 percent) for the end-diastolic, end-systolic gated acquisition with motion display and in 99 of 117 segments (83 percent) for the end-diastolic, end-systolic gated acquisition with photographic display. The multigated display was least accurate in scoring of the apical segment, the end-diastolic, end-systolic gated movie display in scoring of the inferior segment and the end-diastolic, end-systolic gated photographic display in scoring of the apical and septal segments.

Scoring based on multigated blood pool images had a significantly greater percent agreement with results of contrast ventriculography when segments were normal on contrast ventriculography (88 percent) than when they were abnormal (79 percent) (p <0.05). However, analysis of receiver operating characteristics demonstrated similar levels of diagnostic accuracy for the three radionuclide blood pool imaging techniques in predicting abnormal wall motion on contrast ventriculography. Multi-gated cardiae blood pool imaging is a valid and accurate noninvasive means of detecting left ventricular regional wall motion abnormalities. End-diastolic, end-systolic gated blood pool imaging can be reliably used for regional wall motion determination when the equipment necessary for multigated acquisition is not available.     

右外侧小切口剖胸矫治合并心底部畸形的室间隔缺损体会

目的:总结经右外侧小切口剖胸矫治合并心底部畸形的室间隔缺损(VSD)手术方法及临床疗效。方法:总结经右侧剖胸入路矫治合并简单心底部畸形(动脉导管未闭和/或永存左上腔静脉)的VSD 16例(R组),同期经右侧剖胸入路矫治不合并心底部畸形的VSD 144例(C组),R组在矫治心内畸形的同时,游离结扎动脉导管或游离阻断左上腔静脉。通过对比体外循环时间、主动脉阻断时间、术后机械通气时间、术后引流量、监护室时间以及术后住院时间,观察处理简单心底部畸形对手术的影响和治疗效果。结果:与C组相比较R组体外循环时间[(65.31±17.10)vs.(55.02±15.97)min P<0.05]明显延长,但主动脉阻断时间[(33.44±8.02)vs.(31.40±10.12)min]、术后机械通气时间4.25 hvs.13.08 h、术后引流量88.44 mL vs.89.83 mL、监护室时间2.38 d vs.1.95 d、术后住院时间[(7.88±1.82)vs.(7.88±2.30)d],差异无统计学意义。2组均无死亡及严重并发症,C组有8例患儿术后血痰,1例肺部感染;R组2例血痰。结论:经右外侧小切口剖胸入路矫治合并简单心底部畸形的VSD安全可行。     

Perioperative myocardial infarct following aortocoronary bypass. Clinical aspects, causes, consequences

Perioperative infarction is a significant factor of morbidity of coronary bypass surgery. The aim of this study was to review peri-operative infarction and its complications over a 10 year period (1974 to 1984) and to determine its consequences on left ventricular function and life expectancy. The material included 514 patients who underwent coronary bypass surgery. Perioperative infarction was defined as the association of a postoperative Q wave and increase in creatinine phosphokinase after the 24th postoperative hour: this diagnosis was made in 31 cases (Group A), 6 per cent of the series; 483 patients (Group B) had no signs of infarction. The necrosis involved the revascularised zone in 26 cases and other zones in 5 cases. The acute phase of infarction was associated with major complications in 9 patients of Group A. In 22 patients (70 per cent of cases) the initial evolution was uncomplicated. There was no significant difference in the number of patients with unstable angina between Groups A and B (52 per cent vs 67 per cent), with single vessel disease (25 per cent vs 28 per cent), double vessel disease (45 per cent vs 34 per cent) or with triple vessel disease (30 per cent vs 38 per cent). The average number of bypasses was higher in Group A (2.06 per cent vs 1.4 per cent, p less than 0.05), as was the duration of cardiopulmonary bypass (117 min vs 91 min, p less than 0.05) and of aortic clamping (45 min vs 31 min, p. less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Central nervous system manifestations of hyperparathyroidism

Prospective neurologic and psychologic studies were thus undertaken in 19 patients who were to undergo major neck operations either for parathyroidectomy (seven for primary hyperparathyroidism and six for secondary hyperparathyroidism) or other reasons (six control subjects). A complete physical and neurologic examination, laboratory tests (calcium, PTH), roentgenograms, a standard electroencephalogram and psychologic testing were carried out in patients before and three and a half months after neck operation.The preoperative electroencephalograms were abnormal in groups with both primary and secondary hyperparathyroidism. For the patients with primary hyperparathyroidism, the preoperative electroencephalogram revealed a percentage electroencephalographic power below 5 Hz (± SE) of 4.2 ± 2.2 per cent (normal = 2.4 ± 1.0 per cent), and the percentage of electroencephalographic frequencies below 7 Hz was 14.7 ± 3.2 per cent (normal = 6.0 ± 1.6 per cent). Postoperatively, however, there were significant (p < 0.01) decrements in these measurements to normal values. The percentage electroencephalographic power below 5 Hz was 1.5 ± 0.6 per cent, whereas the percentage of electroencephalographic frequencies below 7 Hz was 5.2 ± 1.1 per cent. In patients with secondary hyperparathyroidism, both the percentage electroencephalographic power below 5 Hz (9.7 ± 2.5 per cent, p < 0.01) and the percentage electroencephalographic frequencies below 7 Hz (22.2 ± 4.2 per cent, p < 0.01), were significantly higher than normal values. There were significant decrements in all the abnormal electroencephalographic values postoperatively. The percentage electroencephalographic power below 5 Hz decreased to 3.4 ± 2.4 per cent, and the percentage electroencephalographic frequencies below 7 Hz decreased to 17.4 ± 3.1 per cent. Electroencephalograms in control patients did not change.Patients with primary hyperparathyroidism showed no significant postoperative improvement in any of the psychologic parameters tested. By contrast, patients with secondary hyperparathyroidism showed improvement in several areas of testing after undergoing surgery when compared to control subjects.The brain calcium in four other patients with secondary hyperparathyroidism who died of miscellaneous causes was 38.3 ± 5.7 meq/kg dry wt, versus the normal value of 25.2 ± 0.7 meq/kg dry wt (p < 0.03).These data show that in patients with either primary or secondary hyperparathyroidism, the electroencephalogram is abnormal and shows significant improvement following parathyroidectomy. There is also improvement in several tests of intellectual function in patients with secondary hyperparathyroidism. Brain calcium content was significantly higher than normal in patients with secondary hyperparathyroidism.     

Functional consequences of interventricular septal involvement in right ventricular infarction: Echocardiographic,clinical, and hemodynamic observations

Although ischemic involvement of the interventricular septum (IVS) may occur in patients with right ventricular infarction (RVI), the potential functional significance of such involvement has not been explored. In 10 patients with hemodynamically evident RVI, ischemic involvement of the IVS was assessed by measuring IVS systolic thickening on M-mode echocardiography. Six patients (group I) had decreased IVS systolic thickening, an echocardiographic indicator of ischemia, or infarction, while four (group II) did not. Group I had significantly higher right ventricular filling pressures (19 ± 3 vs 12 ± 5 mm Hg, p = 0.04) and right ventricular end-diastolic echocardiographic dimensions (32 ± 8 vs 20 ± 3 mm; p = 0.02) than group II. Paradoxic septal motion was noted only in group I patients (p = 0.01). Left ventricular filling pressures, left ventricular end-diastolic dimensions, and systolic thickening of the left ventricular posterior wall (LVPW) were not significantly different between the groups. Three group I patients died; all had decreased systolic thickening of both the IVS and LVPW. In each, autopsy confirmed infarction of the right ventricular free wall, IVS, and LVPW. In patients with right ventricular infarction, ischemic involvement of the interventricular septum may have important consequences for both right and left ventricular function.     

Quantitation and significance of horizontal cardiac motion in M mode and two dimensional echocardiography

Cardiac structures are continuously moving during the cardiac cycle so that constantly changing acoustical interfaces are being recorded by the theoretically static echographic beam. The characteristic movement of the base of the heart toward the apex in systole appears as horizontal motion when imaged in two dimensional echocardiographic parasternal long axis views. The quantitative characteristics of horizontal motion were studied in 50 control patients, 25 patients with decreased cardiac output, 20 with volume overload and 10 with pericardial effusion. The angle of cardiac shift at the aorto-interventricular septal junction was 8 ± 2 ° (mean ± standard deviation) in control patients, and this change constituted 21 ± 6 percent of the area within the arc containing the standard M mode information. Horizontal shifts were decreased in patients with decreased cardiac output (4 ± 2 °; p < 0.001) and increased in patients with volume overload (11 ± 4 °; p < 0.001) or pericardial effusion (10 ± 3 °; p < 0.025).With use of the concept of horizontal motion, the interventricular septal hinge point was noted to be in the area of the membranous interventricular septum, rather than at the junction of the upper and middle thirds of the interventricular septum in 80 percent of normal subjects, 72 percent of patients with decreased cardiac output, 60 percent of those with pericardial effusion, 52 percent of those with left-sided volume overload and 40 percent of those with right-sided volume overload. The concept of horizontal cardiac motion was also pertinent to the interpretation of aortic valve opening, the transposition of aortic root information to apparent left ventricular outflow tract level, one form of pseudosystolic anterior mitral motion, abnormal left atrial echoes, echoes mimicking flail posterior mitral leaflet and interpretation of left atrial wall motion at the left atrial-left ventricular junction. In conclusion, horizontal cardiac motion is a significant physiologic phenomenon of potential clinical importance. It causes important changes in the echographic recording of acoustical information.     

External,noninvasive cardiac assistance and nitrate administration for patients with unstable angina pectoris or acute coronary insufficiency

The influence of external, noninvasive counterpulsation, alone and in combination with sublingual nitroglycerin or isosorbide dinitrate, on left ventricular volumes and ejection fractions was investigated. Patients with unstable angina pectoris or acute coronary insufficiency were selected for this evaluation. Left ventricular volumes and ejection fractions were estimated using a gated blood pool scintigraphic technique. Twenty minutes of external counterpulsation did not significantly alter left ventricular end-diastolic volumes, end-systolic volumes, or ejection fractions in 13 patients. When sublingual isosorbide dinitrate (10 mg.) was combined with 20 minutes of external counterpulsation in eight patients, left ventricular end-diastolic volumes decreased 16 ± 7 per cent (p = .05), but neither left ventricular end-systolic volumes (12 ± 7 per cent) nor ejection fractions were significantly changed. When sublingual nitroglycerin (0.4 mg.) was combined with 15 minutes of external counterpulsation in three patients, left ventricular end-diastolic volumes decreased 21 ± 3 per cent (p < .01), end-systolic volumes decreased 25 ± 4 per cent (p < .02), and ejection fractions were not significantly changed. When left ventricular volumes and ejection fractions were measured 30 and 65 minutes after isosorbide dinitrate administration, 10 and 45 minutes after cessation of external counterpulsation, respectively, left ventricular end-diastolic volumes and end-systolic volumes were significantly decreased by approximately 20 per cent while ejection fractions were unchanged. When left ventricular volumes and ejection fractions were measured 25 minutes after nitroglycerin administration, 10 minutes after cessation of external counterpulsation, end-systolic volumes decreased 23 ± 2 per cent (p < .005) and end-diastolic volumes decreased 27 ± 3 per cent (p < .005). No significant changes in left ventricular end-diastolic or end-systolic volumes were seen 60 minutes after nitroglycerin administration. As in the other studies, left ventricular ejection fractions were unchanged. The results suggest that relatively short periods of external, noninvasive cardiac assistance do not alter left ventricular volumes or ejection fractions in patients with unstable angina pectoris or acute coronary insufficiency. Although external counterpulsation combined with a vasodilator such as isosorbide dinitrate or nitroglycerin decreases left ventricular volumes, it offers no advantage over vasodilator treatment alone.     

Effects of digoxin on left ventricular function in coronary artery disease patients

To assess whether digitalis modifies or prevents the deterioration of the left ventricular ejection fraction and wall motion during acute ischemia, we performed gated blood pool radionuclide ventriculograms in 15 patients with angiographically documented coronary artery disease. All patients were studied in the resting state and during maximal supine bicycle exercise, both before and 1 hour after 1 mg intravenous digoxin.There was no significant difference, pre-digoxin vs post-digoxin, in exercise tolerance (415 ± 84 vs 418 ± 107 seconds), number of segments with abnormal resting wall motion (12 vs 11) or exercise wall motion (21 vs 19). Ten patients developed angina during the same exercise load, irrespective of digoxin administration. Twelve patients had subnormal left ventricular ejection fraction during exercise pre-digoxin, vs 13 patients post-digoxin (P = ns). In the resting state, the left ventricular ejection fraction was higher after digoxin (53 ± 14% pre vs 58 ± 14% post, P < 0.05). During exercise, however, the left ventricular ejection fraction was not significantly improved after digoxin (50 ± 16% pre vs 53 ± 17% post, P = ns).These data indicate that although acute administration of digoxin improves the resting left ventricular function, it does not improve exercise tolerance to angina. Furthermore, intravenous digoxin does not appear to prevent the deterioration of left ventricular wall motion and ejection fraction during exercise induced ischemia.