Left Ventricular Regional Wall Motion Abnormalities Research Articles

Acute Neurocardiogenic Injury After Subarachnoid Hemorrhage

Left ventricular (LV) systolic dysfunction has been reported in humans with subarachnoid hemorrhage (SAH), and its underlying pathophysiology remains controversial. Possible mechanisms include myocardial ischemia versus excessive catecholamine release from sympathetic nerve terminals. For 38 months, echocardiography and myocardial scintigraphy with technetium sestamibi (MIBI) and meta-[(123)I]iodobenzylguanidine (MIBG) were performed on 42 patients admitted with SAH to assess myocardial perfusion and sympathetic innervation, respectively. A blinded observer interpreted the scintigraphic images. Cardiac troponin I (cTI) was measured to quantify the degree of myocyte necrosis. Blinded observers calculated the LV ejection fraction and graded each LV segment as normal (score=1), hypokinetic (score=2), or akinetic (score=3). A wall-motion score was calculated by averaging the sum of the 16 segments. All subjects with interpretable scans (N=41) had normal MIBI uptake. Twelve subjects had either global (n=9) or regional (n=3) absence of MIBG uptake. In comparison with patients with normal MIBG uptake, those with evidence of functional denervation were more likely to have LV regional wall-motion abnormalities (92% versus 52%, P=0.030) and cTI levels >1 microg/L (58% versus 21%, P=0.029). LV systolic dysfunction in humans with SAH is associated with normal myocardial perfusion and abnormal sympathetic innervation. These findings may be explained by excessive release of norepinephrine from myocardial sympathetic nerves, which could damage both myocytes and nerve terminals.

Cardiac Injury after Subarachnoid Hemorrhage Is Independent of the Type of Aneurysm Therapy

Subarachnoid hemorrhage (SAH) is associated with cardiac injury and dysfunction. Whether aneurysm clipping versus coiling has a differential effect on the risk of troponin release and left ventricular (LV) dysfunction after SAH is unknown. It is hypothesized that aneurysm treatment does not affect the risk of developing cardiac injury and dysfunction. The study included 172 consecutive SAH patients who underwent clipping (n = 109) or coiling (n = 63) aneurysm therapy. Hemodynamic data were collected, cardiac troponin I was measured, and echocardiography was performed on the 1st, 3rd, and 6th days after enrollment. A cardiac troponin I measurement of more than 1.0 microg/L was considered abnormal. For each echocardiographic examination, a blinded observer measured LV ejection fraction (abnormal if <50%) and quantified LV regional wall motion abnormalities. The incidence of cardiac outcomes in the treatment groups was compared using odds ratios (ORs). The coiled patients were older than the clipped patients (mean age, 59 +/- 13 yr versus 53 +/- 12 yr; t test, P < 0.001) and were more likely to have posterior aneurysms (33% versus 18%; chi(2) test, P = 0.019). There were no significant between-group differences in the risk of cardiac troponin I release (coil 21% versus clip 19%; OR = 0.89, P = 0.789), regional wall motion abnormalities (33% versus 28%; OR = 0.76, P = 0.422), or LV ejection fraction lower than 50% (16% versus 17%; OR = 1.06, P = 0.892). No patient died of cardiac causes (heart failure, myocardial infarction, or arrhythmia). Surgical and endovascular aneurysm therapies were associated with similar risks of cardiac injury and dysfunction after SAH. The presence of neurocardiogenic injury should not affect aneurysm treatment decisions.

Assessment by radionuclide ventriculography of postischemic regional left ventricular dysfunction in patients with healed myocardial infarction or angina pectoris

Postischemic left ventricular (LV) dysfunction has been observed in experimental animal models after brief, complete coronary artery occlusion followed by reperfusion, but less relevant information is available for humans. The incidence and duration of postischemic LV dysfunction was examined by exercise radionuclide ventriculography in 50 patients with coronary artery disease. Cardiac imaging was performed at rest and was repeated during exercise and then immediately after and 5, 10, and 20 minutes after exercise. LV regional wall motion abnormalities were noted in 50 segments during exercise; they persisted in 30 of 50 segments after exercise, and remained apparent for 20 minutes in 11 segments. In contrast, in 33 segments, wall motion abnormalities were noted only after exercise and continued for 20 minutes in 13 of 33 segments. Exercise-related wall motion abnormalities were observed in 63 segments (76%) after exercise, and in 24 of 63 segments abnormalities continued for 20 minutes after exercise, although parameters of LV hemodynamic functions approached normal values after exercise. The mechanism of postexercise dysfunction is considered to involve acute myocardial stunning after a brief episode of myocardial ischemia, whereas regional wall motion abnormalities observed only after exercise seem to be related to increased levels of catecholamines or sympathetic overdrive, which mask less significant myocardial ischemia during exercise.

Echocardiographic Manifestations in Patients with Cardiac Sarcoidosis

Background Cardiac sarcoidosis is a life-threatening disease with protean clinical manifestations, including congestive heart failure (CHF), conduction disturbance, ventricular arrhythmia and sudden death. Nonetheless, it is difficult to diagnose cardiac sarcoidosis in the clinical setting. Some echocardiographic findings of cardiac sarcoidosis associated with other diagnostic tools ( 201 thallium scintigraphy, 67 gallium citrate scan, serum markers and others) may be helpful upon early suspicion and diagnosis of cardiac sarcoidosis. Materials and Methods Fifty-two patients (36 female) with cardiac sarcoidosis, with a mean age of 48 ± 14 years (range, 21–70 yr), underwent a series of echocardiographic follow-up (mean, 88 ± 48 mo) examinations, and important echocardiographic parameters and findings were recorded. Results There were left ventricular (LV) regional wall motion abnormalities (RWMAs) noted in 40 (localized in 16, multiple in 24), dilatation of the LV with impaired LV contractility in 28, thinning of the basal interventricular septum (IVS) in 27, thinning of LV free wall in 18, apical aneurysm in 12, apical thrombus in two, mimicking hypertrophic cardiomyopathy (HCM) in two, pericardial effusion (PE) in two (with cardiac tamponade in one), and LV wall thinning and aneurysm formation after steroid therapy for cardiac sarcoidosis in two of 43 patients. Conclusion Thinning of the basal IVS or LV free wall is a specific echocardiographic finding of cardiac sarcoidosis. Other echocardiographic findings of cardiac sarcoidosis may mimic coronary artery disease (LV RWMA or apical aneurysm), CHF, or HCM. PE and thinning of the LV wall after steroid therapy were also noted in rare situations.

Regional left ventricular wall motion abnormalities in myocardial infarction and mitral annular descent velocities studied with pulsed tissue Doppler imaging

We evaluated global left ventricular (LV) systolic function from mitral annular systolic motion velocities measured by pulsed tissue Doppler imaging in patients with previous myocardial infarction (MI) and LV regional wall motion abnormalities. The subject group consisted of 45 patients with wall asynergies, 3 with ischemic cardiomyopathy, 8 with dilated cardiomyopathy, and 15 healthy control subjects. The peak systolic descent velocity (Sw) and the time from the electrocardiographic Q wave to the peak of the systolic wave (Q-Sw) were measured at 6 mitral annular sites obtained from 2-dimensional apical long-axis, 4-chamber, and 2-chamber echocardiograms; these variables were compared with the LV ejection fraction (EF) calculated from the left ventriculogram. The mean Sw at the sites corresponding to the infarct regions was significantly lower and the mean Q-Sw was significantly longer in the MI groups than in the control group. The mean Sw and Q-Sw at all 6 sites in the ischemic and dilated cardiomyopathy groups were significantly lower and longer, respectively, than those of the control group. There were significant correlations between the EF and the means of the Sw and Q-Sw values at the sites corresponding to the infarct regions in the MI groups. In the ischemic and dilated cardiomyopathy groups, significant correlations existed between the EF and the means of the Sw and Q-Sw values at all 6 sites. Thus the parameters obtained from mitral annular systolic motion velocities with pulsed tissue Doppler imaging reflect LV asynergy corresponding to the infarct regions in patients with MI, and global LV systolic function may be evaluated with these parameters. (J Am Soc Echocardiogr 1998;11:841-8.)

Goal-directed transesophageal echocardiography performed by intensivists to assess left ventricular function: Comparison with pulmonary artery catheterization

Objectives: Transesophageal echocardiography (TEE) is a valuable procedure for assessing left ventricular (LV) function, but it has not been widely applied in critical care because of the limited number of intensivists who are trained in echocardiography. This prospective study was designed to evaluate the feasibility of training intensivists to perform a goal-directed, limited-scope TEE to assess LV function in critically ill patients using a pediatric monoplane TEE probe. A secondary goal was to compare the usefulness of the TEE data with that of data obtained by a simultaneous pulmonary artery catheter (PAC). Design: Prospective, blinded. Setting: University teaching hospital. Participants: One hundred consecutive, intubated, intensive care unit patients. Interventions: Five surgical intensivists with no previous background in echocardiography were trained under the supervision of two cardiologists to perform limited-scope TEE using a monoplane pediatric probe. One intensivist (A) reviewed the PAC data and recorded a diagnostic impression and therapeutic plan. A second intensivist (B), blinded to the PAC data, then performed TEE to determine cardiac volume, LV wall thickness, and LV global and regional wall motion. Intensivists A and B reviewed the data from both PAC and TEE, and intensivist A then formulated a new diagnosis and therapeutic plan. Measurements and Main Results: Intensivists performed 48 TEE examinations under direct supervision of a cardiologist, and 52 without supervision, but reviewed poststudy. The average duration of TEE was 12 ± 7 minutes. The intensivists' interpretations of TEE data were deemed correct in 93% of cases for LV wall thickness, 87% for intracardiac volume status, 81% for regional LV wall motion abnormalities, and 77% for global LV function. When the TEE and PAC technologies were compared, it was found that the TEE data disagreed with.the PAC evaluation of intracardiac volume in 55% of cases and with the PAC assessment of myocardial function in 39% of cases. The post-PAC therapeutic recommendations were different from the post-TEE therapeutic recommendations in 58% of patients. Conclusions: Training intensivists in limited-scope, goal-directed TEE, using a pediatric monoplane probe to evaluate LV function, can be done rapidly and safely, and yield data pertinent to management of critically ill patients even in the early stages of skill acquisition.

Detection of myocardial ischemia by transesophageal echocardiographically determined changes in left ventricular area in patients undergoing coronary artery bypass surgery

Study Objective: To evaluate left ventricular (LV) dimensions and function during myocardial ischemic episodes in anesthetized patients undergoing coronary artery bypass surgery. Design: Prospective, nonrandomized study. Setting: Large, medical school-affiliated tertiary-care medical center. Patients: 36 adults undergoing elective primary coronary artery bypass surgery. Interventions: Transesophageal atrial pacing for 3 to 5 minutes at heart rates (HRs) of 65, 70, 80, and 90 beats per minute. Measurements and Main Results: Arterial, pulmonary artery, and venous pressures, transesophageal echocardiographic (TEE) determined LV end-diastolic (EDA) and end-systolic (ESA) areas, and fractional area change (FAC = [EDA-ESA]/EDA). Myocardial ischemia determined as at least 1 mm ST segment deviation at J + 60 milliseconds from 12-lead electrocardiography (ECG) and TEE detected new LV regional wall motion abnormalities. Biplane TEE images were recorded on videotape, and LV EDA and ESA were determined with planimetry from images of the LV short axis. Myocardial ischemia was observed in 12 patients. In these patients, EDA and ESA were higher and FAC lower than those patients without ischemia at the same HR. There were no differences between patients with and without myocardial ischemia with regard to pulmonary artery occlusion pressure, stroke volume, or other hemodynamic variables. The positive predictive values were best for ESA (67%) and EDA (58%), and least for FAC (18%). Negative predictive values were highest for ESA (85%) and EDA (80%), and least for FAC (47%). Conclusions: In anesthetized patients undergoing coronary artery bypass surgery, myocardial ischemia observed during atrial pacing results in increases in LV dimensions and decreases in FAC compared with values in patients without ischemia. These results support further investigations of the clinical usefulness of monitoring LV EDA and LV ESA with TEE as a method of myocardial ischemia detection.

Predictors of inotropic support during weaning from cardiopulmonary bypass in coronary artery bypass grafting surgery.

Early or prophylactic inotropic drug administration is occasionally required to facilitate separation from cardiopulmonary bypass (CPB) in cardiac surgery. However, it is not without untoward effects and should be conducted on the basis of rational criteria. The purpose of our study was to clarify variables associated with the requirement for inotropic support during separation from CPB and to testify whether pre-CPB left ventricular (LV) function, as evaluated by transesophageal echocardiography (TEE), is one of the significant variables. Clinical profile data and TEE findings were retrospectively analyzed for 91 patients who had received elective primary isolated coronary artery bypass grafting (CABG) surgery. Post-CPB inotropic drug administration initiated prior to aortic decannulation was considered inotropic support for terminating CPB. Stepwise multiple logistic regression analysis identified pre-CPB LV regional wall motion abnormalities (RWMA), NYHA class, age, and duration of CPB (in order of significance) as factors associated with inotropic support for discontinuing CPB. Pre-CPB LV enddiastolic area or fractional area change was not a significant variable in the multivariate model. Our result suggests that evaluation of pre-CPB LV RWMA is useful in predicting the need of inotropic intervention during separation from CPB in patients undergoing CABG surgery.

913-113 Detection of Left Ventricular Involvement with 1-123 MIBG SPECT in Patients with Arrhythmogenic Right Ventricular Dysplasia: Comparison with Electron-beam CT, MRI and Left Ventriculography

Histological, functional abnormalities in the left ventricular (LV) myocardium have been observed in some patients (pts) with arrhythmogenic right ventricular dysplasia (ARVD). It is recently reported that 1 – 123 MIBG (MIBG) SPECT allowed to detect early stage in ARVD. But comparing MIBG SPECT with other noninvasive examination has not been studied. We performed MIBG (111 MBq) SPECT, electron-beam CT (EBCT), MRI and left ventriculography (LVG) in 16 ARVD pts to evaluate the best method forthe early diagnosis of LV involvement. ARVD was diagnosed on the basis of RV wall motion abnormality, left bandle branch block type ventricular tachycardia, and myocardial fatty infiltration and/or fibrosis in RV endomyocardial biopsy. We divided the LV myocardium into 5 segments (apical, anterior, septal, posterior and lateral), and we assessed the findings in each segment. Abnormalities of regional tracer uptake in MIBG delayed (4 hr) SPECT images were evaluated by using the extent bull's-eye map which exhibits reduced %uptake under mean-2SD of 10 normal controls. Abnormal segments in EBCT, MRI and regional wall motion abnormalities (rWM) were highly matched with MIBG defects (93% in EBCT, 100% in MRI and 83% in decreased rWM). Abnormal segments in MIBG, EBCT and MRI were poorly matched with decreased rWM (45% in MIBG, 67% in EBCT and MRI). Fifteen segments which showed MIBG defects revealed no abnormalities in EBCT, MRI and rWM. Massive fatty infiltration detected by EBGT and MRI highly correlated with MIBG defects and decreased rWM. But the sympathetic abnormalities as shown by MIBG defects appeared to precede massive fatty infiltration and rWM abnormalities. a MIBG defects EBCT MRI decreased rWM Pt(n) 14 8 7 8 Abnormal segments 44 15 * 12 * 24 * Matched with MIBG defects - 14(93%) 12(100%) 20 (83%) Matched with decr. rWM 20 (45%) 10(67%) 8(67%) - * p &lt; 0.05 vS. MIBG defects Regional reduction of MIBG myocardial uptake indicating abnormal sympathetic innervation is a very sensitive marker of LV involvement, comparing EBCT, MRI and regional wall motion abnormalities, in ARVD.

Acute cocaine administration induces ventricular regional wall motion and ultrastructural abnormalities in an anesthetized rabbit model

Whether acute doses of cocaine can induce left ventricular (LV) regional wall motion abnormalities in animals with otherwise normal coronary arteries is unknown. We studied rabbits receiving constant cocaine infusions (group I: 0.025 to 1.5 mg/kg/min, n = 10), multiple cocaine boluses (group II: 3–5 mg/kg each bolus, n = 10), or saline (group III; n = 8). In group I rabbits, short-axis LV area and diameter increased by 15% to 40% at 60 minutes compared to baseline and to controls ( p < 0.01), but percentage of global area fractional shortening was unchanged. Eight rabbits in each of groups I and II, but no controls, developed LV regional wall motion abnormalities as detected by echocardiography: 15 (7 hypokinesis and 8 akinesis or dyskinesis) in the anteroseptal and 2 (hypokinesis) in the posterior LV wall. Among rabbits showing LV wall motion abnormalities, anteroseptal fractional shortening and % area reduction averaged > 20% less ( p = 0.03 for area reduction) at 30 minutes versus controls. Only 50% of group I or II rabbits with LV anteroseptal wall motion abnormalities had intraventricular conduction disturbances. Radioactive microsphere flow studies ( n = 6) 1 minute after a 4 mg/kg cocaine bolus revealed an equivalent decrease (10% to 20%, average) in septal and LV free wall perfusion ( p value not significant). Electron microscopy revealed myocardial cell contraction band necrosis in 3 and sarcoplasmic reticular edema in 7 of 10 cocaine rabbits (unrelated to dose). We conclude that acute cocaine administration in rabbits frequently produces LV anteroseptal wall motion abnormalities even in the absence of differentially decreased perfusion or intraventricular conduction disturbances and produces ultrastructural abnormalities of the myocytes. These findings suggest a direct, nonuniform effect of cocaine on the LV myocardium.

Utility of various radionuclide techniques for distinguishing ischemic from nonischemic dilated cardiomyopathy

<h3>Background.—</h3> Clinically, ischemic and nonischemic (idiopathic) dilated cardiomyopathy may be difficult to distinguish. Radionuclide ventriculography and exercise testing with thallium-201 scintigraphy are often used in an attempt to differentiate them noninvasively. With these techniques, the presence of (1) left ventricular (LV) regional asynergy, (2) depressed LV systolic function with normal right ventricular function, and/or (3) thallium-201 perfusion abnormalities traditionally has been regarded as evidence of ischemic heart disease. We assessed the incidence with which these abnormalities occur in patients with nonischemic-dilated cardiomyopathy. <h3>Methods. —</h3> Seventy-six patients (45 men, 31 women, aged 18 to 75 years) with invasively proven nonischemicdilated cardiomyopathy underwent radionuclide ventriculography (n = 75) and provocative thallium-201 perfusion imaging (n = 17). <h3>Results.—</h3> Regional LV wall motion abnormalities were noted in 48% of patients, and 54% had LV systolic dysfunction without concomitant right ventricular dysfunction. Reversible and/or fixed exercise-induced thallium-201 perfusion abnormalities occurred in 94% of the patients studied. <h3>Conclusions.—</h3> Radionuclide ventriculography and exercise testing with thallium perfusion imaging cannot be used reliably to differentiate ischemic from nonischemic dilated cardiomyopathy, since many patients with the latter have radionuclide evidence of LV segmental wall motion abnormalities, selective LV systolic dysfunction, and segmental perfusion abnormalities. (<i>Arch Intern Med</i>. 1992;152:769-772)

Utility of Various Radionuclide Techniques for Distinguishing Ischemic From Nonischemic Dilated Cardiomyopathy

Clinically, ischemic and nonischemic (idiopathic) dilated cardiomyopathy may be difficult to distinguish. Radionuclide ventriculography and exercise testing with thallium-201 scintigraphy are often used in an attempt to differentiate them noninvasively. With these techniques, the presence of (1) left ventricular (LV) regional asynergy, (2) depressed LV systolic function with normal right ventricular function, and/or (3) thallium-201 perfusion abnormalities traditionally has been regarded as evidence of ischemic heart disease. We assessed the incidence with which these abnormalities occur in patients with nonischemic-dilated cardiomyopathy. Seventy-six patients (45 men, 31 women, aged 18 to 75 years) with invasively proven nonischemic-dilated cardiomyopathy underwent radionuclide ventriculography (n = 75) and provocative thallium-201 perfusion imaging (n = 17). Regional LV wall motion abnormalities were noted in 48% of patients, and 54% had LV systolic dysfunction without concomitant right ventricular dysfunction. Reversible and/or fixed exercise-induced thallium-201 perfusion abnormalities occurred in 94% of the patients studied. Radionuclide ventriculography and exercise testing with thallium perfusion imaging cannot be used reliably to differentiate ischemic from nonischemic dilated cardiomyopathy, since many patients with the latter have radionuclide evidence of LV segmental wall motion abnormalities, selective LV systolic dysfunction, and segmental perfusion abnormalities.

Effect on global and regional left ventricular functions by percutaneous transluminal coronary angioplasty in the chronic stage after myocardial infarction

Data are reported on 145 consecutive patients with prior myocardial infarction who had successful percutaneous transluminal coronary angioplasty (PTCA) of the infarct-related artery (5 ± 6 months after infarction), and left ventricular (LV) angiograms before PTCA and during follow-up (7 ± 4 months). There was a significant long-term improvement in LV function, ejection fraction increased from 60 ± 13% to 64 ± 13% (p < 0.001), and regional wall motion abnormalities decreased by 40%. Multivariate discriminant analysis identified reduced LV function and a high degree of stenosis before PTCA as predictors for improvement in LV function (ejection fraction < 60%: ejection fraction from 48 ± 9% to 57 ± 14%, p < 0.001; and stenosis ≥90%: ejection fraction from 59 ± 15% to 66 ± 14%, p = 0.003). Restenosis ≥90% in patients with initial stenosis < 90% decreased ejection fraction from 59 ± 16% to 51 ± 14% (p <0.05). Other factors tested (treatment of infarction by thrombolysis, time between infarction and PTCA, and severity of angina pectoris) had no effect on long-term changes in LV function. It is concluded that successful elective PTCA of a high-grade stenosis in an infarct-related artery may improve LV ejection fraction and regional wall motion abnormalities, especially in patients with impaired LV function.

Left ventricular shape as a determinant of functional mitral regurgitation in patients with severe heart failure secondary to either coronary artery disease or idiopathic dilated cardiomyopathy

The relation between left ventricular (LV) shape and functional mitral regurgitation (MR) was evaluated in 39 patients with congestive heart failure. Heart failure was due to coronary artery disease in 23 patients (group I) and to idiopathic dilated cardiomyopathy in 16 (group II). LV shape was quantitated based on the ratio of LV major-to-minor axis and LV sphericity index calculated at end-systole and end-diastole. In group I, 9 patients had angiographic evidence of MR and 14 did not. In group II, 10 patients had MR and 6 did not. Within each group, there were no differences between patients with and without MR with regard to LV chamber volume and regional segmental wall motion abnormalities. In both groups, however, a significant difference was observed between patients with and without MR with respect to end-systolic and end-diastolic LV shape indexes. In group I, the end-systolic major-to-minor axis ratio was lower in patients with (1.42 ± 0.04) than without (1.72 ± 0.05) MR (p < 0.001). Similar differences were observed in group II (1.41 ± 0.06 vs 1.69 ± 0.04) (p < 0.01). In group I, the end-systolic sphericity index was also greater in patients with (0.32 ± 0.02) than without (0.25 ± 0.01) MR (p < 0.02). Similar differences were observed in group II (0.37 ± 0.03 vs 0.26 ± 0.01) (p < 0.02). These data indicate that in patients with severe heart failure, functional MR is present in those who manifest a more spherical LV cavity.

Ventricular systolic and diastolic impairment during pacing-induced myocardial ischemia in coronary artery disease: Simultaneous hemodynamic, electrocardiographic, and radionuclide angiographic evaluation

This study examined the impairment in systolic and diastolic performance of both ventricles during pacing-induced myocardial ischemia in 12 men with coronary artery disease. Simultaneous hemodynamic, ECG, and radionuclide angiographic assessments were made: pre pacing (pre-P); intermediate pacing (P-1); maximum pacing (P-2); and immediately after pacing (post pacing (P-P). The prepacing measurements were made with the patient in the supine position and during leg elevation. Pacing produced a leftward and upward shift in the diastolic pressure-volume relation, a progressive decrease in left ventricular (LV) end-diastolic volume ( p < 0.003) and right ventricular (RV) end-diastolic volume ( p < 0.01), concomitant with an increase in the pulmonary artery wedge pressure ( p < 0.004) and the right atrial pressure ( p < 0.04). The shift in the LV pressure-volume relation was associated with an initial increase (P-1), followed by a decrease (P-2) in the peak filling rate ( p < 0.001). Pacing also resulted in systolic dysfunction: abnormal LV ejection fraction responses in eight patients, LV regional wall motion abnormalities in eight patients, and abnormal RV ejection fraction responses in seven patients. Leg elevation resulted in a 7% increase in cardiac output, a 20% increase in RV end-diastolic volume, a 28% increase in right atrial pressure, a 29% increase in pulmonary artery wedge pressure, and a 10% increase in LV end-diastolic volume ( p < 0.05). Thus, the ischemic response to pacing results in systolic and diastolic LV and RV dysfunction, with the diastolic impairment being more frequent than the systolic impairment.

Left ventricular dyskinesia reversed by intravenous nitroglycerin: A manifestation of silent myocardial ischemia

Patients with coronary artery disease (CAD) frequently have left ventricular (LV) wall motion abnormalities in the absence of symptoms. Thirty-one patients with such LV wall motion abnormalities in the absence of symptoms participated in a study of the response of these abnormalities to ascending doses of intravenous nitroglycerin (NTG). In a subgroup of 20 patients the relation between the location of LV wall motion abnormalities and the presence or absence of significant CAD (≥50% diameter reduction), in the vessel supplying the LV region, was assessed. Wall motion improved after intravenous NTG; the ejection fraction increased by 3.7% (mean p < 0.05) and by 9.4% in the 19 patients who responded. There was no significant increase in heart rate; both LV systolic and enddiastolic pressures decreased minimally (12.5 and 3.5 mm Hg, respectively, p < 0.05). The ejection fraction response was observed with NTG doses ≤200 μg and no dose-response relation was apparent. In the subgroup subjected to regional wall motion analysis, the presence of dyskinesia was significantly (p = 0.007) associated with the presence of important CAD in a vessel supplying that region. Further, the fact that wall motion improvement after NTG was significantly (p = 0.002) associated supports the concept that silent ischemia results in LV regional wall motion abnormalities, which can be reversed with low dose intravenous NTG.

Echocardiographic assessment of left ventricular wall motion in myocarditis.

Segmental wall motion abnormalities are common in patients with myocarditis. Left ventricular (LV) regional wall motion was assessed in six patients with myocarditis by two-dimensional echocardiography. Some of our patients demonstrated regional thinning of the wall, similar to myocardial infarction. Therefore, segmental wall motion abnormalities with or without regional wall thinning detected by two-dimensional echocardiography cannot be used to differentiate myocarditis from coronary artery disease. Nevertheless, echocardiography can be performed repeatedly and is useful for evaluating the severity of myocarditis by assessing LV regional wall motion abnormalities, changes in LV wall thickness and cardiac pump function during the course of the disease.

Regional left ventricular wall motion abnormalities in chronic volume overload.

Computer-assisted analysis of left ventricular (LV) wall motion has been performed in 12 patients (pts) with chronic volume overload and in seven normal subjects. All pts were in sinus rhythm, without congestive heart failure and without coronary artery disease at selective coronary angiography; 30 degrees right anterior oblique ventriculograms were employed in each case. Thirty-six radiants were automatically traced and the percent shortening of each radiant was calculated using two different reference methods (fix and floating methods). In valvular heart disease (VHD) pts LV volumes were significantly increased, and ejection fraction and LV eccentricity were significantly reduced. LV eccentricity inversely correlated with LV volumes. VHD pts showed regional LV abnormalities. Inferoapical and anterior wall motion was significantly reduced (two-sample t-test P less than 0.05) using the fix method. With this method a significant inverse correlation between percent shortening of the radiants correspondent to the inferoapical region and end-diastolic and end-systolic volumes was found; a significant direct correlation was found with LV systolic eccentricity. Ejection fraction directly correlated with the percent shortening of radiants correspondent to both the anterior and inferior regions. The role of LV "dynamic geometry" alterations as a possible cause for the observed regional LV wall motion abnormalities is emphasized.

Radionuclide Angiocardiographic Measurement of Left Ventricular Volume and Ejection Fraction

In recent years a number of different radionuclidic techniques have been developed to measure left ventricular volume and ejection fraction. Area-measurement concepts have been applied to static and electrocardiographically gated radionuclidic images which have resulted in accurate measurement of left ventricular end-diastolic volume (LVEDV) and ejection fraction (LVEF). Gated (end-diastolic and end-systolic) image analysis has also proven capable of detecting regional left ventricular wallmotion abnormalities in patients with coronary disease. Time-activity curves can be extracted from left ventricular images, and several dynamic techniques have been developed and have also resulted in accurate measurement of LVEDV and LVEF. Radionuclide methods are currently available which are accurate and atraumatic and consequently applicable to the serial study of patients with heart disease. In particular, several of these radionuclide methods are relatively inexpensive and should be able to be performed in most hospitals.