Prognosis in patients with an abnormal exercise radionuclide angiogram in the absence of significant coronary artery disease.

To investigate the prognostic importance of abnormal exercise left ventricular function on radionuclide angiography in the absence of significant angiographic coronary artery disease, 79 consecutive patients with these findings were followed up for a mean of 25 months (range 12 to 55). All patients had 1) an ejection fraction at rest greater than or equal to 0.40, 2) an ejection fraction that decreased with exercise or peak exercise ejection fraction less than 0.60, and 3) no significant coronary artery disease. The mean change in ejection fraction was a decrease of 0.07. In 63 patients (80%), the ejection fraction decreased during exercise; in 45 patients, it decreased by greater than or equal to 0.05. Twenty patients (25%) had a peak exercise ejection fraction less than 0.50. All patients were alive at follow-up study. One patient had a nonfatal myocardial infarction, and three patients were hospitalized for recurrent chest pain. No patient underwent coronary angioplasty or bypass surgery. The calculated infarction-free survival rate at 4 years by life table analysis was 97%. Patients with an abnormal exercise radionuclide angiogram in the absence of significant angiographic coronary artery disease have an excellent short-term prognosis.

Coronary artery venous bypass graft aneurysm with symptomatic coronary artery emboli.

A 53 year old man, asymptomatic for 9 years after aorto-right coronary artery venous bypass surgery, developed two prolonged episodes of myocardial ischemia during a 7 month interval. Diagnostic exercise tests subsequent to each episode were normal. Coronary angiography demonstrated marked dilation with filling defects of the venous bypass graft. A large thrombus-filled venous bypass graft aneurysm was excised at surgery. Spontaneous coronary artery embolization related to a venous bypass graft aneurysm has not been described previously, but may become more frequent as survival and follow-up after coronary bypass surgery lengthen.

Severe exercise-induced ischemia does not identify high risk patients with normal left ventricular function and one- or two-vessel coronary artery disease.

OBJECTIVES: This study was conducted to determine whether severe exercise-induced ischemia identifies high risk patients with a normal left ventricular ejection fraction and one- or two-vessel coronary artery disease. BACKGROUND: Severe ischemia during exercise radionuclide angiography has been shown to identify high risk patients among certain other patient subsets. METHODS: Four hundred twenty patients with left ventricular ejection fraction > or = 50% and one- or two-vessel disease underwent exercise radionuclide angiography within 3 months of coronary angiography. Patients were treated initially with revascularization (n = 140) or medical therapy (n = 280) at the discretion of their physicians. Patients treated with revascularization were more likely to have angina by history, a positive exercise electrocardiogram, a lower exercise ejection fraction, two-vessel disease and proximal left anterior descending coronary artery disease. Two hundred sixty-four of the 280 patients given medical therapy who had complete follow-up data formed the study group. Outcome was compared between patients with (n = 56) and without (n = 208) severe exercise-induced ischemia, defined by previously published criteria (work load < or = 600 kg-m/min, ST segment depression > or = 1 mm and decrease in ejection fraction with exercise). RESULTS: During follow-up, there were 30 initial cardiac events (12 cardiac deaths and 18 nonfatal myocardial infarctions). There was no difference in the 5-year event-free survival rate: 91% in patients with and 87% in patients without severe ischemia (p = 0.89). There was no association between event-free survival and severe ischemia (chi 2 = 1.41, p = 0.24). The study had approximately 80% power at alpha = 0.05 to detect a 25% decrease in event-free survival in the group with severe ischemia. In addition, there was no association between severe ischemia and outcome if late revascularization was included as an event or if the total mortality rate (overall survival) was analyzed. CONCLUSIONS: Severe exercise-induced ischemia fails to identify a high risk subgroup among patients with normal left ventricular function and one- or two-vessel disease who are treated initially with medical therapy.

Natural history of hypertrophic cardiomyopathy in the elderly.

The prognosis of patients diagnosed as having hypertrophic cardiomyopathy at advanced age has not been well defined. This study details follow-up information obtained for 95 patients initially diagnosed as having hypertrophic cardiomyopathy at age greater than or equal to 65 years. Seventy-five percent of patients were symptomatic, as defined by the presence of chest pain, dyspnea or syncope, and the mean ventricular septal thickness was 20 mm. The median duration of follow-up study was 4.2 years. The survival rate at 1 and 5 years was 95% and 76%, respectively, which was not significantly different from that an age- and gender-matched control group. Of patients presenting with New York Heart Association functional class I or II dyspnea, only 18% progressed to class III or IV during the follow-up period. However, patients presenting with class III dyspnea had a 1 year mortality rate of 36%, significantly higher than that of control subjects (p less than 0.003). Of the echocardiographic variables, indexed left atrial size was most strongly associated with reduced survival (p less than 0.008). These results suggest that the prognosis of elderly patients with hypertrophic cardiomyopathy is generally favorable. Certain clinical and echocardiographic variables appear to be of use in identifying patients with a less favorable prognosis.

Prediction of the severity of aortic stenosis by Doppler aortic valve area determination: prospective Doppler-catheterization correlation in 100 patients.

Two-dimensional and Doppler echocardiography was performed prospectively in 100 patients with aortic stenosis who were undergoing clinically indicated cardiac catheterization. The purpose of this study procedure was to determine various Doppler variables predictive of the severity of aortic stenosis and to compare Doppler- and catheterization-derived aortic valve areas. Doppler-derived mean gradient correlated well with corresponding gradient by catheterization (r = 0.86). Peak Doppler aortic flow velocity greater than or equal to 4.5 m/s and Doppler-derived mean aortic gradient greater than or equal to 50 mm Hg were specific (93 and 94%, respectively) for severe aortic stenosis (defined as catheterization-derived aortic valve area less than or equal to 0.75 cm2) but were not sensitive (44 and 48%, respectively). Doppler-derived aortic valve area calculated by the continuity equation correlated well with catheterization-derived aortic valve area calculated by the Gorlin equation when either the time-velocity integral ratio (r = 0.83) or the peak flow velocity ratio (r = 0.80) between the left ventricular outflow tract and the aortic valve was used in the continuity equation. A velocity ratio of less than or equal to 0.25 alone was sensitive (92%) in detecting severe aortic stenosis. Therefore, use of various Doppler-derived values allows reliable noninvasive estimation of the severity of aortic stenosis.

Idiopathic dilated cardiomyopathy in the young: clinical profile and natural history.

The clinical profile and course of documented cases of idiopathic dilated cardiomyopathy in children have been poorly characterized. Twenty-four patients (median age 2 years, range less than 1 month to 18 years) with idiopathic dilated cardiomyopathy were identified from Mayo Clinic records from 1973 to 1982. The most common presentation was congestive heart failure (92% of patients). Echocardiography (22 patients) generally revealed a dilated left ventricle with reduced fractional shortening (mean 14%) and ejection fraction (mean 26%). Two-dimensional echocardiographic evidence of left ventricular thrombus was present in 3 (23%) of 13 patients. Median cardiac index and left ventricular end-diastolic pressure (19 patients) were 2.5 liters/min per m2 and 22 mm Hg, respectively. Myocardial biopsy in eight patients showed nonspecific findings without active inflammation or evidence of endocardial fibroelastosis. On follow-up (mean duration 33 months, range 0 to 149), systemic arterial embolism had occurred in 2 (8%) of 24 patients. Fifteen of 24 patients had died (63% survival at 1 year and 34% survival at 5 years of follow-up). The cause of death was congestive heart failure in 11, complications after cardiac transplantation in 3 and sudden cardiac death in 1. Nine patients are alive at a mean follow-up time of 65 months (range 26 to 149); five are asymptomatic. Serial determination of left ventricular systolic function, available in all survivors, showed improvement in six patients and no significant change in three. Severe mitral insufficiency was present only in patients who ultimately died. A recent viral syndrome was noted more frequently in patients who survived.(ABSTRACT TRUNCATED AT 250 WORDS)

Comprehensive Doppler assessment of right ventricular diastolic function in cardiac amyloidosis.

To assess right ventricular diastolic function in cardiac amyloidosis, pulsed wave Doppler ultrasound measurements of right ventricular inflow velocities and superior vena cava and hepatic vein flow velocities with respiratory monitoring were performed in 41 patients with primary systemic amyloidosis and two-dimensional echocardiographic features of cardiac involvement. Right ventricular diastolic function was abnormal in 31 (76%) of these patients, the major abnormality being a short deceleration time (less than 150 ms) in 21 (68%), suggesting restriction. In contrast, 7 (23%) of the 31 patients had a decreased ratio of early (E) and late (A) diastolic peak flow velocities and a prolonged deceleration time (greater than 240 ms), suggesting abnormal relaxation. The patients were classified into two groups on the basis of right ventricular free wall thickness: group 1, less than 7 mm and group 2, greater than or equal to 7 mm. Compared with normal values, group 1 showed an increased peak late flow velocity (44 +/- 19 versus 39 +/- 6 cm/s; p less than 0.01) and a decreased E/A velocity ratio (1.1 +/- 0.4 versus 1.5 +/- 0.3; p less than 0.01). Group 2 showed a markedly shortened deceleration time (151 +/- 37 versus 225 +/- 28 ms; p less than 0.01), characteristic of restriction. In the overall group, superior vena cava peak flow velocity was decreased in systole and increased in diastole and flow reversals during inspiration were increased compared with normal values. Hepatic venous flow velocities were similar to those in the superior vena cava except for larger flow reversals in the hepatic vein. Thus, in cardiac amyloidosis, right ventricular diastolic function is abnormal. There is a spectrum of right ventricular filling abnormalities and the restrictive filling pattern is seen only in the advanced stages of the disease.

Serial Doppler echocardiographic follow-up of left ventricular diastolic function in cardiac amyloidosis.

A spectrum of left ventricular diastolic filling abnormalities noted on Doppler echocardiography has been demonstrated in patients with cardiac amyloidosis. To determine how these filling abnormalities evolve over time and the significance of any change, serial pulsed wave Doppler studies of left ventricular inflow were performed over 12.6 +/- 4.9 months in 41 consecutive patients (36 men and 15 women, mean age 59 +/- 11 years) with typical two-dimensional echocardiographic features of cardiac involvement. The measurements were peak left ventricular inflow in early diastole (E) and atrial contraction (A) velocities, E/A ratio, deceleration time and isovolumetric relaxation time. Patients were classified by mean left ventricular wall thickness into an early group (less than 15 mm) of 24 patients and an advanced group (greater than or equal to 15 mm) of 17 patients. The total group showed an increased E/A ratio (1.7 +/- 0.9 versus 1.4 +/- 0.9, p = 0.009) and decreased deceleration time (164 +/- 57 versus 174 +/- 51 ms, p = 0.11) at follow-up compared with baseline study. The early group showed significant changes in the E/A ratio (1.6 +/- 1.0 versus 1.2 +/- 0.7, p = 0.001) between the two studies. Seven patients (29%) in the early group showed a change from an abnormal relaxation or "normal" pattern to one of restriction, coincident with increased symptoms in six of these patients. Fifteen (88%) of the 17 patients in the advanced group did not show significant changes in the measures during the follow-up study, but these patients already showed a restrictive pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized comparison of the nephrotoxicity of iopamidol and diatrizoate in high risk patients undergoing cardiac angiography.

Three hundred seven high risk patients with renal impairment (serum creatinine greater than or equal to 1.5 mg/dl) were randomized in a double-blind manner to either iopamidol (a nonionic, low osmolar radiocontrast agent) or diatrizoate (a conventional radiocontrast agent) at cardiac angiography with subsequent follow-up study of renal function. Baseline clinical and angiographic variables were similar in the iopamidol (n = 155) and diatrizoate (n = 152) groups. Change in renal function after angiography was less pronounced with iopamidol compared with diatrizoate as measured by mean ( +/- SD) increase in 24 h serum creatinine (0.11 +/- 0.2 versus 0.22 +/- 0.26 mg/dl, p less than 0.001), mean maximal increase in serum creatinine (0.2 +/- 0.44 versus 0.38 +/- 0.73 mg/dl, p less than 0.0001) and percent of patients with a maximal increase in serum creatinine greater than 0.5 mg/dl (8% versus 19%, p less than 0.01). Such differences could not be documented in diabetic patients using insulin. There was no significant difference between agents in the number of patients developing clinically severe acute renal dysfunction. It is concluded that iopamidol is less nephrotoxic than diatrizoate in high risk patients at cardiac angiography. However, the difference in nephrotoxicity is small, of no major clinical significance in the majority of high risk patients and could not be documented in insulin-using diabetic patients. Iopamidol may be the preferred agent in certain patients with advanced renal impairment, but further study is warranted.

Risk stratification of single or double vessel coronary artery disease and impaired left ventricular function using exercise radionuclide angiography.

Patients with 3-vessel coronary artery disease (CAD) and normal left ventricular (LV) function have a worse prognosis if they manifest ischemia during exercise testing. The present study determines if exercise radionuclide angiography can aid in the risk stratification of patients with 1- or 2-vessel CAD and impaired LV function (ejection fraction less than 50%). Sixty-five consecutive patients with these findings were followed for a median duration of 24 months (range 12 to 49). Eleven of the 65 patients (17%) had severely ischemic exercise radionuclide angiograms, defined as: a decrease in ejection fraction with exercise; greater than or equal to 1.0 mm of ST-segment depression; and peak exercise workload less than or equal to 600 kg-m/min. During follow-up 11 patients had initial significant cardiac events: 4 cardiac deaths, 1 cardiac arrest, 4 myocardial infarctions and 2 bypass or angioplasty procedures for unstable angina greater than or equal to 3 months after the exercise study. Four of 11 patients (36%) with severely ischemic exercise radionuclide angiograms had events, compared to 7 of 54 patients (13%) without ischemic radionuclide angiograms. Event-free survival at 18 months was 73% for patients with severe exercise ischemia versus 92% for those without ischemia (p less than 0.05). Univariate analysis showed that severe ischemia on radionuclide angiography was the only variable of several tested that significantly predicted future cardiac events (chi-square = 8.16, p less than 0.005). Among patients with 1- or 2-vessel CAD and impaired resting LV function, severe ischemia on exercise radionuclide angiography identifies a subgroup at high risk for future cardiac events.

Two-dimensional echocardiographic findings in systemic sarcoidosis.

The records of 88 patients with systemic sarcoidosis who underwent 2-dimensional echocardiography were reviewed to define the typical echocardiographic abnormalities in patients with clinical evidence of cardiac involvement. Twelve patients (14%) had echocardiographic evidence of left ventricular systolic dysfunction attributed to cardiac sarcoidosis (segmental hypokinesis in 8 patients and global hypokinesis in 4 patients). A high incidence of congestive heart failure (9 of 12) and conduction system disease (7 of 12) was characteristic of these patients. The remaining 76 patients had normal echocardiograms or abnormalities attributed to nonsarcoid sources. In 8 (11%) of these 76 patients, there were significant clinically unexplained conduction abnormalities likely related to sarcoidosis.

Myocarditis related to drug hypersensitivity.

Hypersensitivity myocarditis is an inflammatory disease of the myocardium usually related to a drug allergy. The clinical manifestations may be nonspecific, and the diagnosis is seldom suspected or established during life. We report a case that demonstrates both typical and atypical features of this disease and review the clinicopathologic correlations. This case illustrates the potential occurrence of both electrical conduction block and ventricular tachyarrhythmias, either of which may account for the mechanism of sudden death in these patients. When cardiac symptoms or electrocardiographic abnormalities (or both) occur in a setting consistent with drug allergy, hypersensitivity myocarditis should be considered. Treatment consists of discontinuation of use of the drug responsible for the reaction and, possibly, administration of corticosteroids and immunosuppressive therapy.

Prognostic value and limitations of exercise radionuclide angiography in medically treated coronary artery disease.

We investigated whether exercise radionuclide angiography provides prognostic information in addition to that identified by resting left ventricular function and coronary anatomy in patients with medically treated coronary artery disease. Clinical follow-up (median, 21.7 months) was obtained in 424 medically treated patients who underwent exercise radionuclide angiography and coronary angiography. The mean age of the study population was 58 years, and 67% were men. Cardiac death occurred in 16 patients, nonfatal myocardial infarction in 16, and nonfatal out-of-hospital cardiac arrest in 1. Univariate analysis showed that multiple variables were associated with future cardiac events, including number of diseased vessels, exercise and rest radionuclide ejection fraction, history of myocardial infarction, exercise and rest left ventricular end-systolic and end-diastolic volume indices, peak exercise workload, age, abnormal resting electrocardiogram, and peak exercise ST-segment depression. Only three variables were independently associated with cardiac events on follow-up: number of diseased vessels, radionuclide ejection fraction at rest, and age. In patients with three-vessel disease and a resting radionuclide ejection fraction of more than 40%, a subgroup with higher risk could not be identified on the basis of exercise radionuclide response.

Absence of severe exercise-induced ischemia does not identify low-risk patients with three-vessel coronary artery disease.

The purpose of this study was to determine the prognosis of medically treated patients with three-vessel coronary artery disease and normal left ventricular function who do not have severe ischemia on exercise radionuclide angiography. The absence of severe ischemia was defined prospectively (in accordance with previously published criteria) as the presence of at least one of the following: (1) workload more than 600 kg-m/min, (2) ST-segment depression of less than 1 mm, or (3) unchanged or increased left ventricular ejection fraction during exercise. Of 42 patients (33% in functional class III or IV) followed up for a median duration of 53 months (range, 1 to 84 months), 22 had initial cardiac events during follow-up, including 6 cardiac deaths, 5 nonfatal myocardial infarctions, and 11 late (a median of 29 months after the exercise study) coronary revascularization procedures. At 4 years of follow-up, the overall survival was 83%. Survival free of cardiac death or myocardial infarction was 77%, and survival free of all cardiac events was 59%. Even in the absence of severe exercise-induced ischemia, medically treated patients with three-vessel coronary artery disease and normal left ventricular function still have a poor long-term outcome.

Successful treatment of pulmonary embolism and associated mobile right atrial thrombus with use of a central thrombolytic infusion.

Patients with pulmonary embolism and two-dimensional echocardiographic evidence of right atrial thrombus have a high mortality rate despite standard anticoagulation therapy. We used a direct central infusion of streptokinase in three such patients, who subsequently had rapid and complete clinical improvement. In this setting, thrombolytic therapy should be considered an effective therapeutic option.

Impaired left ventricular function, one- or two-vessel coronary artery disease, and severe ischemia: outcome with medical therapy versus revascularization.

OBJECTIVE: To determine whether patients with impaired left ventricular function and one- or two-vessel coronary artery disease who manifest severe ischemia during exercise radionuclide angiography have a lower rate of subsequent cardiac events when initial management is revascularization rather than medical therapy. DESIGN: During a median follow-up of 100 months, we compared the outcome between 37 patients who underwent a revascularization procedure and 22 who received medical therapy at the Mayo Clinic between September 1980 and December 1985. MATERIAL AND METHODS: The revascularization therapy consisted of coronary artery bypass grafting in 31 patients and coronary angioplasty in 6. Overall survival and survival free of initial cardiac events were compared statistically for the medically and surgically treated patients. RESULTS: Eleven deaths occurred in the patients who received medical therapy and 9 in the revascularization group. Five-year overall survival was 58% in the medically treated patients versus 84% in the revascularization group. A significant association was noted between type of treatment and overall survival (adjusted chi 2 = 6.20; P = 0.013). Twenty patients had initial cardiac events--7 in the medically treated group (3 cardiac deaths and 4 nonfatal myocardial infarctions) and 13 in the revascularization group (3 cardiac deaths, 3 out-of-hospital cardiac arrests, and 7 nonfatal myocardial infarctions). Survival free of cardiac events at 5 years was 72% in the medically treated patients and 66% in those who underwent revascularization. No association was detected between type of treatment and survival free of cardiac events. CONCLUSION: These nonrandomized data suggest that overall survival for patients with one- or two-vessel coronary artery disease, impaired left ventricular function, and severe exercise-induced ischemia may be improved by revascularization, but the subsequent cardiac event rates are not.

Permanent cardiac pacing after the Fontan procedure.

Permanent cardiac pacing after a Fontan procedure is complicated by complex cardiovascular anatomy. Of 332 patients undergoing the Fontan procedure at the Mayo Clinic, we evaluated 15 who postoperatively required permanent pacing (mean age 16.5 years, range 4 to 31 years). Underlying congenital cardiac defects included univentricular heart in nine patients, double-outlet right ventricle in three, and tricuspid atresia in three. The indication for pacing was postoperative heart block in seven patients, congenital heart block in five, postoperative sick sinus syndrome in two, and heart block because of previous operation in one. Pacemakers were implanted immediately postoperatively in 11 patients and 12 to 57 months later in four patients. VVI systems were used in nine patients, DDD in four, AAI in one, and a Medtronic Activitrax VVI in one. All ventricular leads were epicardial. Four atrial leads were transvenous endocardial and one was epicardial. Three patients died 4, 9, and 69 months later of causes unrelated to pacing. Among the 12 survivors, mean follow-up was 34 months (range 1 to 107 months). Two patients had a total of three episodes of loss of ventricular capture because of increased chronic thresholds. Our current approach to pacing after a Fontan procedure includes (1) intraoperative placement of temporary atrial and ventricular electrodes, (2) intraoperative attachment of a permanent ventricular epicardial lead for congenital or surgically induced high-grade atrioventricular block, (3) postoperative insertion of transvenous atrial leads if dual-chamber pacing is indicated, and (4) use of programmable pulse generators with high output capability.

Traumatic left ventricular false aneurysm with significant regurgitation from left ventricular outflow tract to left atrium: delineation by two-dimensional and color flow Doppler echocardiography.

A 22-year-old man was asymptomatic 23 months after an automobile accident but had clinical evidence of progressive mitral insufficiency. Two-dimensional and color flow Doppler echocardiography demonstrated a false aneurysm adjacent to the left ventricular outflow tract and significant regurgitation of blood through a traumatic channel from the left ventricular outflow tract to the left atrium. The patient underwent successful surgical closure of the false aneurysm and repair of the traumatic left atrial regurgitation.

Age-related prevalence of valvular regurgitation in normal subjects: a comprehensive color flow examination of 118 volunteers.

We prospectively assessed the influence of aging on the prevalence of valvular regurgitation by using color flow imaging. One hundred eighteen healthy volunteers (21 to 82 years old) had a two-dimensional Doppler echocardiographic study that included color flow imaging to assess valvular regurgitation and that was semiquantitated by mapping the dimensions of the color flow regurgitant jet in orthogonal views. The subjects were divided into two groups: group 1 consisted of subjects who were younger than 50 years old (n = 61), and group 2 consisted of subjects who were at least 50 years old (n = 57). Mitral regurgitation was detected in 57 (48%) of the 118 subjects: 24 subjects (39%) in group 1 and 33 subjects (58%) in group 2. The severity of mitral regurgitation was trivial to mild. Aortic regurgitation was detected in 13 (11%) of the 118 subjects, all in group 2. The severity was trivial to mild. Tricuspid regurgitation was detected in 77 (65%) of the 118 subjects: 35 (57%) in group 1 and 42 (74%) in group 2. The severity was trivial to mild. Pulmonary regurgitation was detected in 24 (31%) of 78 subjects: nine (22%) in group 1 and 15 (41%) in group 2. The severity was trivial. These findings suggest that valvular regurgitation of a trivial or mild degree is a frequent finding in normal subjects and that it increases with age.

Rupture of the left ventricular free wall following mitral valve replacement for mitral stenosis: a cause of complete (fatal) or contained (false aneurysm) cardiac rupture.

Complete or incomplete left ventricular free wall rupture is a known complication of mitral valve replacement. Complete free wall rupture may result in fatal bleeding, whereas incomplete rupture may result in the formation of a pseudoaneurysm with survival possible. Two necropsy patients are described illustrating both of these complications. Proposed mechanisms for injury to the left ventricular free wall are reviewed.