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Background: Despite decreasing rates of acute and subacute complications of percutaneous coronary intervention (PCI), these procedures are generally only performed in centers where it is possible for failed PCI to be treated by rescue coronary artery bypass graft (CABG). Case reports and case series have documented successful PCI following failed CABG. We sought to confirm this decrease in the need for rescue CABG following failed PCI and to examine trends in the utilization of rescue PCI following failed CABG., Hypothesis: The interface between interventional cardiologist and cardiac surgeon is characterized by changing practice patterns and resource utilization., Methods: We examined the medical records of all patients admitted to the Brigham and Women's Hospital over a 7-year period and identified 169 patients who required both PCI and CABG during the same hospital admission. We describe and compare three predetermined groups of patients defined by the sequence of, and indication for, the relevant myocardial revascularization procedures., Results: In all, 100 patients required CABG for failed PCI, 46 patients had planned hybrid procedures involving both CABG and PCI, and 23 patients required PCI following failed CABG. There was a decrease in the need for rescue CABG following failed PCI, both in total numbers and as a percentage of total cases (2.5% in 1994 and 0.22% in 1999). There was a simultaneous increase in the utilization of rescue PCI following failed CABG (0% in 1994 and 1.6% in 2000). Hybrid procedures were identified as a source of innovative solutions to a variety of challenging clinical problems., Conclusions: Changing patterns of resource utilization should be considered when planning hospital facilities and patient triage, and these patients undergoing percutaneous or surgical revascularization may benefit from close cooperation between the cardiac surgeon and the interventional cardiologist.

The case of a young man with spontaneous vasospasm at two sites in his left anterior descending coronary artery is described. Intravascular ultrasound demonstrated mild eccentric atherosclerosis with smaller total artery cross-sectional area (defined as the external elastic membrane) compared with reference segments. Impaired compensatory enlargement (remodeling) in response to mild atherosclerosis may derive from one or more biologic mechanisms that are also responsible for vasospasm. This characteristic is easily identified by intravascular ultrasound. In this case, coronary stenting of the vasospastic sites led to excellent long-term control of symptoms more than 1 year after intervention.

The unique physical properties of the short-lived inert and freely diffusing isotope 81mkrypton allow a continuous observation to be made of regional myocardial perfusion. Eighteen dogs were anaesthetised and a reversible snare placed on the left anterior descending coronary artery (LAD). 81mKrypton was used to study regional myocardial perfusion, and myocardial metabolism was assessed using the epicardial ECG and release of creatine kinase activity (CK). Six dogs did not undergo LAD occlusion ("sham operated"); in six other dogs the LAD was occluded (controls), and another six dogs were given propranolol, 0.5 mg/kg, 20 min after LAD occlusion. All the parameters were measured before and for 5 h after LAD occlusion. When compared to controls, dogs treated with propranolol showed significant improvement (p less than 0.01) in regional myocardial perfusion; smaller loss of electrically active myocardium for any given degree of early ST-segment elevation; and a delay in the release of CK activity from a local coronary vein. These results suggest that propranolol exerts a beneficial effect following the development of acute myocardial infarction.

A technique of recording electrocardiographic maps after exercise is described. This technique allows a measurement to be made of the area of ST segment changes that are projected onto the front of the chest after exercise. A comparison of the sensitivity and specificity of this technique with the orthogonal lead system and a single chest lead showed that praecordial exercise mapping was significantly superior to the other two lead systems in the diagnosis of ischaemic heart disease and may help in identifying patients with extensive disease. In addition information obtained from praecordial exercise mapping can be used to increase the data that are obtained from Holter monitoring of ST segments. The place of the technique in the management of medical and surgical treatment remains to be evaluated.

The physical and biological properties of 201thallium (Tl) have been investigated and are discussed in this review. A new technique using the ultra-short lived 81mkrypton (81mKr) as a continuous infusion into the aortic root in dogs and man is described. This provides a dynamic assessment of changes in regional myocardial perfusion. Experiments using 201Tl and 81mKr in dogs have shown that regional decreases in myocardial perfusion alone cannot be detected in images of the heart using 201Tl. The effects of perfusion and a variety of factors on the energy dependent cellular uptake of 201Tl are discussed as being of primary importance in changing the regional myocardial distribution of this tracer. The constant infusion of 81mKr in patients with anginal chest pain provides continuous measurement of regional myocardial perfusion in high spatial resolution images. This dynamic method provides a physiological assessment of stenosed coronary arteries at rest and during stress.

This study investigates the use of propranolol and nifedipine in the treatment of angina pectoris. The clinical response and the effects on the precordial 16-lead electrocardiogram before and after exercise were studied in 52 patients with frequent angina pectoris. Relief of chest pain and abolition of exercise-induced ST-segment depression was achieved in 16 patients on treatment with propranolol alone (mean dose, 300 mg/d). Of the remaining 36 patients, the precordial area and severity of exercise-induced ST-segment depression were unchanged in 8 patients, of whom 2 reported they were free from chest pain, improved in 10 patients of whom 4 reported they were free of chest pain, and abolished in 14 patients, all of whom were free from chest pain following treatment with both propranolol and nifedipine (mean dose, 50 mg/d). Four patients were unable to tolerate this combination. This study has shown that in patients who do not respond to treatment with propranolol alone the combination of propranolol and nifedipine can be used to control not only anginal pain, but also the precordial electrocardiographic manifestations of ischemia.