Myocardial preservation with alternate coronary artery occlusion and reversal of flow through collateral vessels.

In 1980, a 46-year-old man suffered occlusion of his left anterior descending coronary artery with preservation of myocardium due to collateral flow from a patent right coronary artery. Six years later, unstable angina recurred, this time due to right coronary occlusion but with myocardial preservation due to reversal of collateral flow from his now recanalized left anterior descending artery.

Aneurysm of the pulmonary artery as a cause of severe chest pain.

A 35-year-old man came to the emergency room with severe prolonged precordial chest pain. Serial chest roentgenograms obtained over a ten-year period revealed gradual development of marked aneurysmal dilatation of the pulmonary artery. Impending rupture of the artery was feared in spite of the presence of normal pulmonary artery pressure. At surgery, a markedly dilated pulmonary artery without evidence of rupture was found and the size was reduced by aneurysmorrhaphy. Prompt and continued relief of symptoms was achieved thereafter. Severe chest pain can be an initial symptom of pulmonary artery aneurysm in the absence of rupture, such pain arising either from pain receptors in the wall of the pulmonary artery or possibly from pressure on contiguous mediastinal structures.

Anatomic and prognostic significance of new T-wave inversion in unstable angina.

The significance of the development of new T-wave inversion was studied in 118 consecutive patients with unstable angina. The electrocardiograms during hospitalization in the coronary care unit were analyzed for occurrence of new T-wave inversion greater than or equal to 2 mm and correlated with findings at coronary angiography (73 patients) and at follow-up (112 patients). Twenty-nine patients had anterior T-wave inversion. Of these, 25 patients (86%) had greater than or equal to 70% diameter reduction of the left anterior descending (LAD) artery, compared with 11 (26%) of 42 patients without anterior T-wave inversion (p less than 0.001). The sensitivity of T-wave inversion for significant LAD stenosis was 69%, specificity 89%, and positive predictive value 86%. Two patients had T-wave inversion in the inferior leads. Both patients had significant right coronary artery disease, compared with 18 of 55 patients without inferior T-wave inversion (difference not significant [p = NS]. Seventy-one patients who were treated medically had 16 +/- 9 months' follow-up. Of 26 patients who had T-wave inversion, 10 (38%) had cardiac events, compared with 7 (16%) of the remaining 45 patients without T-wave inversion (p less than 0.05). Forty-one patients who had undergone coronary bypass surgery had 19 +/- 9 months' follow-up. Of 22 patients with T-wave inversion, 4 (18%) had cardiac events, compared with 2 (11%) of the remaining 19 patients without T-wave inversion (p = NS). Thus, development of new T-wave inversion greater than or equal to 2 mm in patients with unstable angina (1) is predictive of significant coronary artery stenosis, and (2) identifies a subgroup with poor prognosis when treated medically.

Coronary artery dissection secondary to coronary arteriography: presentation of three cases and review of the literature.

Three cases of coronary artery dissection secondary to coronary arteriography are presented. Two of these include autopsy material demonstrating medial degeneration in the coronary arteries, which may have predisposed these arteries to dissect. The literature on catheter-induced coronary artery dissection is reviewed and an analysis is presented.

Diagnostic criteria for acute myocardial infarction in patients undergoing coronary artery bypass surgery.

Current techniques for diagnosing perioperative myocardial infarction were studied in 58 patients who underwent coronary bypass surgery. All patients had preoperative and postoperative ECGs and technetium-99m stannous pyrophosphate myocardial scintigrams; serum CK-MB was measured immediately after surgery and daily for 3 days. Postoperative bypass graft visualization and left ventriculography were performed before hospital discharge in every patient. Nine patients (16%) had new Q waves postoperatively. Five of these nine patients had positive pyrophosphate scintigrams, postive CK-MB and new wall motion abnormalities, and the remaining four had negative CK-MB, negative phyrophosphate scintigrams and no new wall motion abnormalities. Seven patients (12%) had newly positive postoperative pyrophosphate scintigrams, positive CK-MB and new wall motion abnormalities on postoperative ventriculography, but only four had new Q waves postoperatively. Eight patients (14%) had new wall motion abnormalities; seven had positive pyrophosphate scintigrams and all had positive CK-MB, but only five had new Q waves. Sixteen patients (28%) had positive CK-MB, including all patients with either positive pyrophosphate scintigrams or new wall motion abnormalities, Eight patients had positive CK-MB without other evidence of perioperative infarction. A newly positive postoperative pyrophosphate scintigram is more senstive and specific than the development of new postoperative Q waves for the diagnosis of hemodynamically significatn perioperative myocardial in farction. CK-MB is highly sensitive, but too nonspecific to be useful for the diagnosis of perioperative infarction.