Holmium:YAG laser transmyocardial revascularization relieves angina and improves functional status.

BACKGROUND: Transmyocardial revascularization (TMR) surgery uses laser channeling of diseased myocardium to treat ischemia and angina. Rigorous prospective randomized studies have been previously unavailable. METHODS: Forty-three patients were randomized to a medication group and 43 to a group scheduled for TMR surgery and medication. All had advanced cardiac ischemia with CCSA class 3 or 4 angina, took at least 2 cardiac medications at maximum doses, and were ineligible for angioplasty or bypass. RESULTS: Forty-two of 43 TMR group patients received surgery and were discharged after hospitalizations averaging 3.2 days. Two suffered perioperative MIs, with one death. Four others died within 12 months of surgery, 3 from cardiac events and 1 from pneumonia. Five medical group patients died from cardiac events within 12 months. Three, 6, and 12 month exams showed angina class improvement in TMR patients compared to preoperative values (3.86 +/- 0.05 vs 1.71 +/- 0.2, P < 0.0001), and to controls at 12 months (3.77 +/- 0.07 vs 1.71 +/- 0.2, P < 0.0001). Exercise tolerance improved in TMR patients over preoperative values, and was better than medication group scores after 12 months (490 +/- 17 sec. vs 294 +/- 12 sec., p = 0.0002). CONCLUSIONS: Holmium:YAG laser channeling of the myocardium improves function and reduces angina in advanced cardiac patients who lack alternative therapeutic options.

Surgical myocardial revascularization.

In conclusion, surgical myocardial revascularization has utilized diverse methods to increase blood flow to the starving myocardium. These methods initially used the microcirculation as the portal to reach myocytes until angiography showed that the obstructions were macrovascular. This resulted in a 30-year era of direct attack on the coronary blockages by coronary bypass. Surgical conduits unfortunately have longevity considerably less than that of native arteries and are limited in number. Alternative conduits, both biologic and prosthetic, have not yet proved to have the same clinical results as the ITA. More patients are living long enough to have the extensiveness of their disease exhaust conventional therapies. Newer therapy, restricted thus far to untreatables, revisits the microcirculation by making laser channels. These many innovative procedures have benefited hundreds of thousands of patients. They emerged from the probity and innovation of many individual surgeons.

Cerebral oxygenation during warming after cardiopulmonary bypass.

OBJECTIVES: To evaluate jugular venous oxygen saturation (SjVO2), measured with a fiberoptic oximetry catheter, and brain tissue oxygen saturation, measured by near-infrared spectroscopy (NIRSO2), as monitors of cerebral oxygenation during cardiopulmonary bypass surgery. DESIGN: Prospective, clinical study. SETTING: Operating room of a Veterans Administration Hospital. PATIENTS: Nineteen patients undergoing moderate hypothermic cardiopulmonary bypass surgery. INTERVENTIONS: SjvO2 and NIRSO2 were monitored in the patients during the surgical procedure. MEASUREMENTS AND MAIN RESULTS: Moderate hypothermic cardiopulmonary bypass surgery had two distinct cerebral hemodynamic phases. While the patients were hypothermic, SjvO2 averaged 80 +/- 7% and none of the patients had an increase in cerebral lactate production. During the rewarming period, however, reductions in SjvO2 to < 50% occurred in 16 (84%) patients and increased cerebral anaerobic metabolism developed in 11 (58%) patients. SjvO2 during rewarming was dependent on mean arterial pressure, with 60 mm Hg appearing to be a critical value. Two other factors appeared to also contribute to the jugular desaturation, a low hematocrit and a rapid warming time. The SjvO2 catheter had excellent performance during the surgery. The average difference between paired measurements of SjvO2 by the catheter and in blood samples was -0.4 +/- 4.25%, and the correlation between the two measurements was highly significant (r2 = .93; p < .001). The NIRSO2 trended with the SjvO2 in most patients (r2 = .63; p < .001). CONCLUSIONS: The study confirms other studies showing that jugular venous desaturation can occur during rewarming after cardiopulmonary bypass surgery. Presently, SjvO2 appears to be a better monitor of cerebral oxygenation than NIRSO2. However, NIRSO2 has promise as a noninvasive monitor of cerebral oxygenation if future developments allow more quantitative measurements of oxygen saturation.