Determinants of 10-year survival after primary myocardial revascularization.

The first 1000 patients undergoing primary isolated myocardial revascularization each year from 1971 to 1978 were analyzed to elucidate the determinants of long-term survival. Five-year survival was 93.2%, and 10-year survival was 79.3%. Five-year survivals were 96.1%, 94.2%, 92.1%, and 90.8%, respectively, for single, double, triple, and left main disease. Ten-year survivals for the same subsets were 88.6%, 83.0%, 74.9%, and 70.9%. Five-year survivals were 95.3%, 92.4%, 88.0%, and 81.3% for patients with normal, mild, moderate, and severe impairment of the left ventricle. Ten-year survivals for the same subsets were 84.1%, 76.5%, 65.8% and 53.6%. Patients receiving internal mammary artery grafts had 95.6% and 85.8% 5- and 10-year survivals that were superior to 92.0% and 76.2% in patients with only vein grafts. Patients completely revascularized had 95.0% and 82.5% 5- and 10-year survivals, while incompletely revascularized patients had lower (90.5% and 75.2%) 5- and 10-year survivals. Advancing age was the most important factor influencing late survival. Other risk factors in descending order of significance were impaired left ventricular function, no mammary artery graft, smoking, abnormal EKG, three vessel or left main disease, left ventricular end diastolic pressure (LVEDP) greater than 24, hypertension, 1971 to 1974 surgical era, cholesterol greater than 300, incomplete revascularization, and two vessel disease.     

An 11 Year Evolution of Coronary Arterial Surgery (1967-1978)

All patients who underwent isolated myocardial revascularization procedures from 1967-70 (n = 741) were compared with the first 1,000 patients who received similar elective operations each year from 1971 through 1978. Data from these eight years were processed through a computerized cardiovascular information registry. Median age increased from 50 to 56 years, multiple-vessel disease increased from 44 to 89%, and left ventricular asynergy from 41 to 54%. The number of grafts per patient increased from 1.5 to 2.5 and yet morbidity declined in every category except neurologic deficit. Operative mortality was 1.1% from 1967 through 1978 and 0.9% from 1971 through 1978. Graft patency was determined for 475 patients from 1967-70, 553 patients from 1971, 519 from 1972, and 540 from 1973. Patency rates after a mean catheterization interval of 21 months were 77, 77, 84, and 87% respectively. Higher graft patency coincides with introduction of the internal mammary artery graft. Five year follow-up was completed for the 1967-1970 series and 1971, 1972, and 1973 cohorts. Actuarial five year survival was 89.6, 91.6, 93.2, and 91.7%. Five year survival comparisons between 1967-1970 patients and 1971-1973 patients in single-, double-, and triplevessel disease categories show significant extended longevity in the later experience. Abnormal ventricular function and incomplete revascularization adversely influenced longevity (p < 0.05) in all years surveyed. In those series the percentage of asymptomatic patients at five years was 66, 65, 69, and 67%. Lower risk and higher five year survival are attributed to greater technical experience, changing technology, and improved management rather than to selection of lower risk cases.     

Endovascular repair of thoracic aortic lesions with the Zenith TX1 and TX2 thoracic grafts: intermediate-term results

PURPOSE: This prospective study was designed to assess the technical success and outcome after patients with thoracic aortic pathology at high risk for conventional therapy were treated with the Zenith TX1 and TX2 endovascular graft. METHODS: Between 2001 and 2004, patients at high risk for conventional surgical therapy presenting with chronic aortic dissections, thoracic aneurysms, or aortobronchial or aortoesophageal fistulas were treated with a single- or multiple-piece endovascular grafts. Surgical modification of proximal or distal fixation sites was performed when necessary to establish adequate regions for device landing zones. Follow-up studies included radiographic evaluation before discharge and at 1, 6, 12, and 24 months. Aortic morphologic characteristics were determined by using three-dimensional imaging studies and centerline of flow measurements. Statistical analyses were performed with Kaplan Meier analysis to assess survival, factors predictive of poor outcome, and morphologic changes, including sac shrinkage. RESULTS: A total of 100 patients (42% women) were treated, including 81 aneurysms, 15 aortic dissections (with aneurysms), 2 patients with fistulous connections (1 aortobronchial and 1 aortoesophageal), 1 subclavian artery aneurysm, and 1 aortic rupture. Mean follow-up and aneurysm size were 14 months and 62 mm, respectively. Most patients (55%) had undergone prior aortic aneurysm repair. Surgical modifications were required to create adequate implantation sites in 29% patients, including 14 elephant trunk/arch reconstructions, 18 carotid-subclavian bypasses, and 4 visceral vessel bypasses. Iliac conduits were required in 19 patients. Overall mortality was 17%, and aneurysm-related mortality was 14% at 1 year. Sac regression (>5 mm maximum diameter decrease) was observed in 52% and 56% at 12 and 24 months. Growth was noted in one patient (1.6%) at 12 months. Endoleaks were detected in eight patients (8.5%) at 30 days and three patients (6%) at 12 months. Secondary interventions were required in 15 patients. Migration (>10 mm) of the proximal or distal stent was noted in three patients (6%) (two proximal and one distal), none of which required treatment or resulted in an adverse event. CONCLUSIONS: Acceptable intermediate-term outcomes have been achieved in the treatment of high-risk patients in the setting of both favorable and challenging anatomic situations with these devices. The complexity of the patient population, in contrast to endovascular infrarenal repair, attests to the differences in the pathophysiology aortic disease in the anatomic beds.     

Growth inhibition as indicator of stress because of atrazine following multiple toxicant exposure of the freshwater macrophyte, Juncus effusus L

Atrazine is a herbicide used most frequently in North America, but it usually is encountered in mixtures of agrochemicals. Few atrazine exposure studies have been conducted using mixed pesticides; therefore, little data are available to suggest reliable means of discerning effects attributable to atrazine. The common freshwater macrophyte, Juncus effusus L., was exposed in 66 mesocosms to atrazine at two nominal concentrations (96 and 192 microg/L) with varying concentrations of chlorpyrifos, monosodium methanearsonate, and monomethylmercury. Exposure levels represented typical levels that might follow runoff or direct-spray application in enclosed waterbodies. Using shoot density and number of shoots shorter than 25 cm per unit area as response measurements, the growth effects of atrazine, even in varying pesticide mixes, could be detected as early as 16 d after initial exposure. Further growth effects specifically caused by atrazine also could be detected following a second exposure to the same toxicant mixture. Mesocosm tests offer greater control of natural variability than would be found in the natural environment and offer more realistic conditions than traditional laboratory/greenhouse studies. Therefore, in field testing, growth measurements should be accompanied by other confirmatory tests, such as pesticide concentrations in tissue and, possibly, chlorophyll concentrations, for measuring specific toxic effects of atrazine and other pesticides.