Martin J. Conley

The prognostic spectrum of left main stenosis.

SUMMARY Three-year survival for 163 consecutive medically treated patients with 50% or greater left main stenosis was 50%. Survival was significantly higher for patients with 50 to 70% left main stenosis (one and three-year survivals of 91% and 66%) than for patients with 70%o or greater left main stenosis (one and three-year survivals of 72% and 41%). In fact, left main lesions of less than 70% were not associated with the increased risk usually attributed to patients with left main stenosis. A number of noninvasive and catheterization characteristics were significant predictors of survival for patients with 70% or greater left main stenosis. Noninvasive descriptors defined a low risk subgroup (one and three-year survivals of 97% and 74%) and a high risk subgroup (one- and three-year survivals of 59%o and 25%). These observations have important implications both in assessing therapeutic interventions and in managing individual patients.

Hospital discharge one week after acute myocardial infarction.

Sixty-seven consecutive patients who had suffered an acute myocardial infarction but no serious complications during the first to fourth hospital days were considered for a trial of hospital discharge at one week. Thirty-three of the 67 patients were discharged at one week, the remainder having a mean hospital stay of 11 +/- 2 days. The incidence of late complications and recurrent infarctions, as well as mortality and functional status, were determined in all patients six months after discharge. No serious complications occurred in either subgroup within three weeks after discharge. There were no deaths in either subgroup and no difference in functional status at six months. Patients without serious complications during the four days after an acute myocardial infarction can be spared the economic costs and psychologic stress of prolonged hospitalization.

The prognostic significance of 50% coronary stenosis in medically treated patients with coronary artery disease.

In this study we determined the prognostic significance of 50% coronary stenosis in 1183 medically treated patients with coronary artery disease. Clinical outcome was measured by survival and eventfree (freedom from death and infarction) rates. Significant disease was first defined as 75% or greater narrowing. In 225 patients with less than 75% narrowing of all vessels, including 68 patients with 50% stenosis of at least one vessel, the 3-year survival rate was 100%. Patients with one, two or three significantly (75% or greater) stenosed vessels with additional 50% stenosed vessels had the same outcome as patients with one, two or three diseased vessels without additional 50% stenosed vessels. Significant disease was then defined as 50% or greater narrowing. Patients with significant (50% or greater) stenosis of one, two and three vessels and the left main coronary artery were divided into those in whom all diseased vessels were 75% or greater stenosed (group A) and those in whom at least one vessel was only 50% stenosed (group B). In every category, group B patients had a better outcome than group A patients. The largest differences were in three-vessel and left main coronary artery disease. Group B patients also had lower prevalences of previous infarction and abnormal ventricular function than group A patients. In three-vessel disease, the differences in outcome between group A and group B patients remained significant in multivariable analyses with descriptors of left ventricular function. Thus, 50% coronary stenosis is associated with less risk than 75% or greater stenosis even after adjustment for left ventricular function. When 50% stenosis is defined as significant, subsets based on the number of diseased vessels may be heterogenous with respect to baseline characteristics and outcome.

Accuracy and interobserver variability of coronary cineangiography: A comparison with postmortem evaluation

The accuracy of interpretation of coronary cineangiography by two independent observers was tested against postmortem findings in 27 patients who died within 6 months of cardiac catheterization. Variations in cineangiographic interpretations between the angiographers were also evaluated. Two patients had normal coronary arteries, while the remaining 25 patients had significant coronary artery disease. Significant stenosis was defined as 75% or greater reduction in luminal diameter. Of 326 coronary segments that could be evaluated postmortem, 15% could not be evaluated cineangiographically. The respective overall accuracy of the two observers was 89 and 88% with an accuracy of 96 and 100% for the left main coronary artery, 91 and 93% for the left anterior descending artery, 84 and 86% for the right coronary artery and 89 and 79% for the left circumflex coronary artery. Cineangiographic assessment of luminal status distal to a significant proximal lesion was possible in more than 70% of major vessels with accuracy levels of 86% for both observers. Of 96 distal vessels inadequately opacified cineangiographically, 49 (52%) were found to be free of significant lesions. Both angiographers agreed in their assessment of 86% of the 340 coronary segments. Interobserver agreement was significantly better for the left main, right and left anterior descending coronary arteries than for the left circumflex coronary artery (p less than 0.05). Accuracy was 93% for 244 segments that were adequately opacified and assessed the same by both angiographers. Cineangiography can thus be used to evaluate coronary anatomy with a high degree of accuracy and minimal interobserver variability.

Cardiac Arrest Complicating Acute Myocardial Infarction: Predictability and Prognosis

Eleven percent of 905 consecutive patients with acute myocardial infarction admitted to the coronary care unit at Duke University Medical Center experienced cardiac arrest. Subgroups of patients at high and low risk for cardiac arrest were identified. Cardiac arrest was experienced by 17 percent of patients with signs of heart failure on admission but by only 3 percent of patients without diabetes mellitus, prior myocardial infarction or heart failure by history or on admission. Only 59 percent of patients with cardiac arrest survived hospitalization compared with 88 percent of those without cardiac arrest. Long-term survival for the 765 hospital survivors was significantly greater in the group without than in the group with arrest at each yearly interval from 1 through 5 years; the 2 year survival rate was 50 and 77 percent, respectively, in these two groups. Many of the deaths among the hospital survivors occurred in patients with signs of heart failure during hospitalization. Among 668 hospital survivors who had mild or no heart failure during hospitalization, cardiac arrest continued to be a significant predictor of mortality. The mode of death among hospital survivors did not differ in the groups with and without cardiac arrest; for example, the incidence rate of sudden death in the two groups was 44 and 37 per cent, respectively. In light of recent reports suggesting that the prophylactic use of antiarrhythmic agents can virtually eliminate virtually fibrillation during the hospital phase of acute myocardial infarction, we contend that such use may substantially reduce both long-term and hospital mortality after acute myocardial infarction.

Complete and incomplete revascularization at aortocoronary bypass surgery: Experience with 392 consecutive patients

Abstract This report presents our experience with “complete” and “incomplete” revascularization in 392 consecutive patients undergoing aortocoronary artery bypass surgery. Patients were considered to have had “complete” revascularization only if all major coronary arteries with 70 per cent occlusion received at least one bypass graft. Patients were considered “incompletely” revascularized if any vessel with a 70 per cent or more occlusion did not receive at least one bypass graft. The “completely” revascularized cohort contained 186 patients and the “incompletely” revascularized cohort contained 206 patients. The survival of the “completely” and “incompletely” revascularized cohorts was compared postoperatively and at 6, 12, and 24 months using the Chi-square test. Relief of anginal pain rates were compared at 6, 12, and 24 months using the Chi-square test. Analyses were repeated after stratifying for number of vessels diseased. The subgroup with one vessel diseased was, by definition, “completely” revascularized. No significant difference in survival or relief of anginal pain was demonstrated in the total group or in subgroups with 2 and with 3 vessels diseased. The data indicate that “complete” revascularization is not closely coupled to two-year survival or relief of anginal pain.

Spectrum of Pulmonary Sequestration

Bronchopulmonary sequestration was diagnosed in 17 patients ranging in age from newborn to 64 years. The sequestration was intralobar in 14 patients and extralobar in 3. The spectrum of symptoms could be divided into three patterns: no symptoms (6 patients), respiratory problems (8 patients), and cardiovascular problems (3 patients). Cardiovascular problems usually manifest themselves in the first few weeks or months of life and often have a respiratory component. In older patients the sequestration is first manifested by recurrent pulmonary infections or, if it remains uninfected, an asymptomatic density on chest roentgenogram. The definitive diagnostic study is arteriography. Operative treatment for the intralobar variety consists of segmental resection or, if the inflammatory process is more extensive, lobectomy. An extralobar sequestration may simply be excised.

Hypersensitive Carotid Sinus Syndrome Manifested as Cough Syncope

We describe a patient with cough syncope who was found to have carotid sinus hypersensitivity with mixed cardioinhibitory and vasodepressor responses. Symptoms were ameliorated by denervation of the more hypersensitive carotid sinus. Spontaneous atypical Wenckebach cycles in this patient were caused by the combined hypersensitive cardioinhibitory and vasodepressor responses. This report stresses the importance of checking blood pressure as well as heart rate in all pa‐tients in whom carotid sinus syndrome is suspected.

Syncope Secondary to Paroxysmal High Grade AV Block in a Heavily Trained Man

J.B. is a well‐trained male with syncope due to paroxysmal AV nodal heart block who ultimately required a permanent pacemaker despite an initial attempt at cessation of training only. Baseline sinus node function was normal, but AV nodal conduction remained abnormal even after autonomic blockade supporting intrinsic AV nodal dysfunction. This case illustrates that vigorous physical training may unmask previously unrecognized intrinsic dysfunction of AV nodal conduction or, as previously reported for physical training induced sinus node dysfunction, cause AV nodal dysfunction. Simple cessation of training to treat this problem is often recommended but may not be adequate for some patients who remain at risk for recurrent syncope during the deconditioning period.