Surgical revascularization of acute (1 hour) coronary occlusion: blood versus crystalloid cardioplegia.

This study compares blood versus crystalloid cardioplegia in restoring contractile function, and high-energy phosphate and tissue water content in a myocardial segment after 1 hour of coronary artery occlusion. Anesthetized dogs underwent instrumentation with the chest open to measure left ventricular and aortic pressures, and systolic shortening in the myocardium perfused by the left anterior descending coronary artery (LAD) was measured with ultrasonic crystals. In 21 dogs, the LAD was occluded for an hour, thereby replacing systolic shortening with passive lengthening averaging -28.7 +/- 6.2% of control shortening in both groups. The dogs were then placed on total bypass, and arrest was achieved with multidose crystalloid (N = 10) or blood cardioplegia (N = 11). The ligatures were released just prior to the second infusion of cardioplegic solution. Postischemic subendocardial levels of adenosine triphosphate were comparably depleted with crystalloid and blood cardioplegia (55.2% and 44.0%, respectively, of control). Subendocardial increases in water content were similar for crystalloid (3.62%) and blood (3.16%) cardioplegia. Recovery of segmental shortening was significantly greater with blood than crystalloid cardioplegia (31.5 +/- 8.2% versus 4.9 +/- 6.6% of control, respectively). We conclude that the composition and the delivery of blood cardioplegia used in this study restore greater postischemic function than crystalloid cardioplegia in acute evolving myocardial infarction.

Intrapulmonary foreign body: sponge retained for 43 years.

We present a patient who had a left thoracotomy 43 years previously. Since that surgery he experienced intermittent hemoptysis, and a recent thoracotomy revealed an intrapulmonary foreign body (retained sponge) in the left lower lobe. The liability potential of this case is discussed.

Immediate functional recovery and avoidance of reperfusion injury with surgical revascularization of short-term coronary occlusion.

Functional recovery with surgical revascularization of acutely ischemic myocardium has not been compared with its nonsurgical counterpart in experimental preparations of coronary occlusion. This study compares the functional and metabolic recovery of ischemic (1 hr coronary occlusion) segments revascularized either by restoration of coronary patency (simulating nonsurgical recanalization, e.g., angioplasty) or by surgical revascularization with multidose hypothermic potassium blood cardioplegic solution. Twenty-two anesthetized open-chest dogs were instrumented with Millar micromanometer-tip catheters to measure left ventricular and aortic pressures. Piezoelectric ultrasonic dimension gauges were implanted in the subendocardium supplied by the left anterior descending coronary artery to measure segmental contractile function. In five dogs, only biopsy samples were obtained for control measurements of ATP, creatine phosphate, and tissue water content. In the remaining 17 dogs, the left anterior descending artery and collaterals were ligated for 1 hr. The ligatures were removed in eight dogs and coronary perfusion continued for 2 hr, simulating nonsurgical reperfusion. The remaining nine dogs were placed on cardiopulmonary bypass and the hearts were arrested for 1 hr with multidose (every 20 min) blood cardioplegic solution enhanced with glutamate and aspartate, simulating surgical revascularization (coronary artery bypass grafting). The coronary ligatures were not released until the second cardioplegic infusion, simulating graft placement. One hour of coronary occlusion placed 39.4 +/- 2.5% of the left ventricle at risk, and converted active systolic shortening to persistent paradoxical bulging (25.2 +/- 2.2% to -5.8 +/- 1.2% systolic shortening).(ABSTRACT TRUNCATED AT 250 WORDS)

Ticlopidine versus aspirin and dipyridamole: influence on platelet deposition and three-month patency of polytetrafluoroethylene grafts.

In an attempt to establish a specific drug regimen that would retard neointimal fibrous thickening (NFT) and promote patency of small arterial grafts, we studied acute platelet accumulation and 3-month patency of 4 mm polytetrafluoroethylene (PTFE) grafts in dogs treated with oral aspirin (2 mg/kg/day) in combination with dipyridamole (5 mg/kg/day) (ASA/D) or ticlopidine (25 mg/kg/day) (T). After 3 days of treatment, 15 dogs were given indium 111-labeled autologous platelets and then had bilateral femoral artery grafts placed (control, 10 grafts; each drug group, 10 grafts). The calculated graft radioactivity expressed as average counts per 10 minutes +/- standard error of the mean (SEM) was as follows: control = 542,003 +/- 63,991; ASA/D = 135,163 +/- 14,443 (p less than 0.001, Student's t test); T = 104,650 +/- 14,004 (p less than 0.001). Bilateral femoral artery and carotid artery grafts were placed in 15 other dogs (control, 20 grafts; each drug group, 20 grafts). Three months later the 60 grafts were excised and their patency recorded: control = 20% (4 of 20 grafts); ASA/D = 70% (12 of 17 grafts) (p less than 0.01, chi-square analysis); T = 30% (6 of 20 grafts) (p greater than 0.05). Mean anastomotic NFT +/- SEM of each graft was measured with an ocular micrometer: control = 1.6 +/- 0.2 mm; ASA/D = 0.7 +/- 0.2 mm (p less than 0.001, Student's t test); T = 1.3 +/- 0.2 mm (p greater than 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)