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Biomedical subjects

B W Lytle

Publications and source records attributed to B W Lytle.

At least 19 recordsLinked to original sources

Sustained angina relief 5 years after transmyocardial laser revascularization with a CO(2) laser.

BACKGROUND: Although transmyocardial laser revascularization (TMR) has provided symptomatic relief of angina over the short term, the long-term efficacy of the procedure is unknown. Angina symptoms as assessed independently by angina class and the Seattle Angina Questionnaire (SAQ) were prospectively collected up to 7 years after TMR. METHODS: Seventy-eight patients with severe angina not amenable to conventional revascularization were treated with a CO(2) laser. Their mean age was 61+/-10 years at the time of treatment. Preoperatively, 66% had unstable angina, 73% had had >/=1 myocardial infarction, 93% had undergone >/=1 CABG, 42% had >/=1 PTCA, 76% were in angina class IV, and 24% were in angina class III. Their average pre-TMR angina class was 3.7+/-0.4. RESULTS: After an average of 5 years (and up to 7 years) of follow-up, the average angina class was significantly improved to 1.6+/-1 (P=0.0001). This was unchanged from the 1.5+/-1 average angina class at 1 year postoperatively (P=NS). There was a marked redistribution according to angina class, with 81% of the patients in class II or better, and 17% of the patients had no angina 5 years after TMR. A decrease of >/=2 angina classes was considered significant, and by this criterion, 68% of the patients had successful long-term angina relief. The angina class results were further confirmed with the SAQ; 5-year SAQ scores revealed an average improvement of 170% over the baseline results. CONCLUSIONS: The long-term efficacy of TMR persists for >/=5 years. TMR with CO(2) laser as sole therapy for severe disabling angina provides significant long-term angina relief.

Adult↗

Double valve endocarditis.

BACKGROUND: There are little data concerning surgical outcomes in patients with native valve endocarditis affecting both the aortic and mitral valves. METHODS: From 1977 to 1998, 54 patients had simultaneous aortic and mitral valve grafting for native valve endocarditis. In 78%, mitral valve involvement was limited to the anterior leaflet, suggesting a jet lesion from the aortic valve. Surgical strategies included 31 valve repairs and valve replacement with mechanical (34), bioprosthetic (34), or allograft (9) prostheses. Three hundred twenty-five patient-years of follow-up were available for analysis (mean 6.0 +/- 4.8 years). RESULTS: There were no hospital deaths. Ten-year survival was 73%. Ten-year freedom from recurrent endocarditis was 84%, with risk peaking at 3 months, followed by a constant risk of 1.3%/yr. Choice of valvar procedure did not influence mortality or reinfection risk. CONCLUSIONS: The most common pattern of double valve infection was a jet lesion on the anterior mitral leaflet. Surgical treatment has late survival and freedom from reinfection similar to those of patients with single heart valve infection.

Adolescent↗

Off-pump reoperative coronary artery bypass grafting by thoracotomy: patient selection and operative technique.

BACKGROUND: Reoperative coronary artery bypass grafting (CABG) in patients with contraindications to sternotomy or cardiopulmonary bypass (CPB) presents a technical challenge. In this study we reviewed patient selection, operative technique, and early results in patients having redo-CABG to the circumflex artery system by a thoracotomy without CPB. METHODS: From January 1996 through December 1999, 21 patients with contraindications to conventional redo-CABG had target vessel revascularization off-pump by thoracotomy. A posterolateral thoracotomy approach was used. RESULTS: No patient required sternotomy or CPB. There was no hospital mortality. Postoperative cardiac morbidity included non-Q wave myocardial infarction (5%), need for intraaortic balloon pump support postoperatively (5%), and atrial fibrillation (5%). Two grafts were studied early and two were studied late (more than 6 months later). One venous graft was found to be occluded early. Survival at 2 years was 95%. Ninety percent of surviving patients were in New York Heart Association functional class I or II. CONCLUSIONS: This approach was associated with no mortality, low morbidity, and favorable early symptomatic improvement. This is the approach of choice in cases of reoperative CABG to the circumflex system when resternotomy or CPB are undesirable, and the culprit coronary vessels are accessible through a thoracotomy.

Aged↗

Safety and efficacy of intraarterial thrombolysis for perioperative stroke after cardiac operation.

BACKGROUND: Acute ischemic stroke after cardiac operations is a devastating complication with limited therapeutic options. As clinical trials of thrombolysis for acute ischemic stroke exclude patients with recent major surgery, the safety of intraarterial thrombolysis in this setting is unknown. METHODS: Thirteen patients with acute ischemic stroke within 12 days of cardiac operation underwent intraarterial thrombolysis within 6 hours of stroke symptom onset. The National Institutes of Health Stroke Scale was used to assess neurologic recovery. RESULTS: The mean age was 69 years (standard deviation +/-5 years) and 62% were men. Cardiac procedures included valve operations in 6 patients, coronary artery bypass grafting in 4, valve and coronary artery bypass grafting in 2, and left ventricular assist device in 1 patient. Atrial fibrillation occurred in 5 patients (38%). The mean time from operation to stroke was 4.3 days (standard deviation +/- 3 days). Thrombolysis was initiated within 3.6 hours (standard deviation +/-1.6 hours) of stroke symptom onset. Recanalization was complete in 1 patient, partial in 5, and 7 patients had low flow. Neurologic improvement occurred in 5 patients (38%). One patient needed a chest tube for hemothorax, 2 others were transfused for low hemoglobin. No operative intervention for bleeding was necessary. CONCLUSIONS: In select patients with acute ischemic stroke after recent cardiac operation, intraarterial thrombolysis appears to be reasonably safe and may lead to neurologic recovery.

Aged↗

Is repair preferable to replacement for ischemic mitral regurgitation?

OBJECTIVE: This study was undertaken to compare mitral valve repair and replacement as treatments for ischemic mitral regurgitation. METHODS: From 1985 through 1997, a total of 482 patients with ischemic mitral regurgitation underwent either valve repair (n = 397) or valve replacement (n = 85). Patients more likely (P < or =.01) to undergo repair had functional mitral regurgitation or coronary revascularization with an internal thoracic artery graft; those more likely to receive valve replacement were in higher New York Heart Association functional classes or underwent emergency operations. These factors were used for multivariable propensity matching. Risk factors for early and late death were identified by multivariable, multiphase hazard function analysis. RESULTS: Within the propensity-matched better-risk group, survivals after valve replacement were 81%, 56%, and 36% at 30 days, 1 year, and 5 years, but survivals after repair were 94%, 82%, and 58% at these intervals (P =.08). In contrast, within the poor-risk group, survivals after repair and replacement were similar (P =.4). Risk factors (P < or =.01) included older age, higher functional class, greater wall motion abnormality, and renal dysfunction. Approximately 70% of patients were predicted to benefit from repair; the benefit lessened or was negated if an internal thoracic artery graft was not used, if a lateral wall motion abnormality was present, or if the mitral regurgitation jet pattern was complex. Freedom from repair failure at 5 years was 91%. CONCLUSION: Late survival is poor after surgery for ischemic mitral regurgitation. Most patients with ischemic mitral regurgitation benefit from mitral valve repair. In the most complex, high-risk settings, survivals after repair and replacement are similar.

Aged↗

HDL cholesterol level predicts survival in men after coronary artery bypass graft surgery: 20-year experience from The Cleveland Clinic Foundation.

BACKGROUND: HDL cholesterol (HDL-C) is an important independent predictor of atherosclerosis, yet the role that HDL-C may play in the prediction of long-term survival after CABG remains unclear. The risk associated with a low HDL-C level in post-CABG men has not been delineated in relation to traditional surgical variables such as the use of arterial conduits, left ventricular function, and extent of disease. METHODS AND RESULTS: We performed a prospective, observational study of 432 men who underwent CABG between 1978 and 1979 in whom preoperative HDL-C values were available. Baseline lipid and lipoprotein values, history of diabetes mellitus and hypertension, left ventricular ejection fraction, extent of disease, and use of internal thoracic arteries were recorded. Hazard ratios (HRs) were determined in the patients with and without a low HDL-C level, which was defined as the lowest HDL-C quartile (HDL-C </=35 mg/dL). After adjustment for age, as well as for baseline metabolic parameters and surgical variables just noted, HDL-C corresponded to both overall (HR 0.40, CI 0.20 to 0.83, P:=0.01) and event-free (HR 0.41, CI 0.24 to 0.70, P:=0.001) survival. Patients with a high HDL-C level (>35 mg/dL) were 50% more likely to survive at 15 years than were patients with low HDL-C level (</=35 mg/dL) (74% versus 57% adjusted survival, respectively; HR 1.72, P:=0.005). In addition, HDL-C showed a strong effect on time-to-event survival such that patients with an HDL-C level of >35 mg/dL were 50% more likely to survive without a subsequent myocardial infarction or revascularization (HR 1.42, P:=0.02). CONCLUSIONS: HDL-C is an important predictor of survival in post-CABG patients. In this study of >8500 patient-years of follow-up, HDL-C was the most important metabolic predictor of post-CABG survival. One third fewer patients survive at 15 years if their HDL-C levels are </=35 mg/dL at the time of CABG. The measurement of HDL-C provides a compelling strategy for the identification of high-risk subsets of patients who undergo CABG.

Cholesterol, HDL↗

Relation of serum triglyceride levels to survival after coronary artery bypass grafting.

We performed a prospective observational study on 6,602 subjects (94% for 5 years and 34% for 10 to 15 years) who underwent coronary artery bypass graft surgery (CABG) between 1982 and 1992. We examined whether triglyceride concentrations adjusted for other factors (total cholesterol, history of diabetes mellitus, systemic hypertension, left ventricular function, number of coronary arteries significantly narrowed, and use of the internal thoracic arteries) explained total and event-free survival. These analyses were duplicated within gender (1,354 women and 5,248 men). This approach allowed a determination of any gender-related disparities in lipid predictors. Triglycerides in the highest quartile were associated with an increased risk of mortality of 20% (confidence interval [CI] 1.0 to 1.4). Similar risk was seen for event-free survival. Although there was no evidence of gender differences in adjusted survival (p = 0.33), a gender by triglyceride interaction (p = 0.004) indicated that the response to high triglycerides as related to survival did differ by gender. Specifically, women had a dramatically higher risk (hazard ratio [HR] 1.5, CI 1.1 to 2.1) than men (HR 1.1, CI 0.9 to 1. 3). Both men and women did have triglyceride-associated risk with regard to event-free survival (HR in men 1.2, CI 1.1 to 1.4; HR in women 1.4, CI 1.1 to 1.8). Examination of high-density lipoprotein cholesterol in a subcohort did not eliminate the observed triglyceride effects. Thus, triglyceride baseline values are primary determinants (similar to baseline left ventricular function or extent of coronary disease) for long-term total and event-free mortality after CABG in women but not in men.

Aged↗

Early onset prosthetic valve endocarditis: the Cleveland Clinic experience 1992-1997.

BACKGROUND: We reviewed all cases of early onset prosthetic valve endocarditis (EO-PVE) occurring less than 12 months after valve operation among 7,043 patients undergoing heart valve replacements or repairs at The Cleveland Clinic between 1992 and 1997. METHODS: Cases were defined by the Duke criteria and identified through prospective surveillance. RESULTS: Seventy-seven cases of EO-PVE were identified (1 per 100 procedures), and during the study period the incidence of EO-PVE decreased from 1.5% (1992 to 1994) to 0.7% (1995 to 1997) (p < 0.01). The incidence of EO-PVE for rings (0.2%; 4 of 1,992) was significantly lower than for mechanical (1.6%; 28 of 1,731) and bioprosthetic valves (1.1%; 41 of 3,320) (p < 0.001). The incidence of EO-PVE was also significantly lower for mitral valve versus aortic valve surgeries (0.6% versus 1.4%, p < 0.001). The most common pathogens causing EO-PVE were coagulase-negative staphylococci (52%), fungi (13%), Staphylococcus aureus (10%), and enterococci (8%). Patients undergoing combined surgical and medical treatment of EO-PVE had a significantly higher 30-day, 2-year, and 3-year survival than medically treated patients, although patients judged to be too ill to survive surgery accounted for two-thirds of the patients treated medically. CONCLUSIONS: There is a 1% incidence rate of EO-PVE among patients undergoing valve operations at our institution, usually caused by coagulase-negative staphylococci, and combined surgical and medical treatment is associated with improved survival compared with medical treatment alone.

Adolescent↗

Cardiac valve replacement in patients on dialysis: influence of prosthesis on survival.

BACKGROUND: Mechanical valves have been recommended for patients on dialysis because of purported accelerated bioprosthesis degeneration. This study was undertaken to determine time-related outcomes in dialysis patients requiring cardiac valve replacement. METHODS: From 1986 to 1998, 42 patients on chronic preoperative dialysis underwent valve replacement; 17 received mechanical valves and 25 received bioprostheses. Age was similar in both groups: 54+/-18.5 years (mechanical) and 59+/-15.5 years (bioprosthetic, p = 0.4). Sites of valve replacement were aortic (27), mitral (11), and aortic and mitral (4). Follow-up was 100% complete. RESULTS: Survival at 3 and 5 years was 50% and 33% after mechanical valve replacement, and 36% and 27% after bioprosthetic valve replacement (p = 0.3). Four patients with bioprostheses required reoperation: 3 for allograft endocarditis and 1 at 10 months for mitral bioprosthesis degeneration. One patient who received a mechanical valve required reoperation. CONCLUSIONS: Prosthetic valve-related complications in patients on dialysis were similar for both mechanical and bioprosthetic valves. Because of the limited life expectancy of patients on dialysis, bioprosthesis degeneration will be uncommon. Therefore, surgeons should not hesitate to implant bioprosthetic valves in these patients.

Adult↗

Interposition vein graft for giant coronary aneurysm repair.

Coronary aneurysms in adults are rare. Surgical treatment is often concomitant to treating obstructing coronary lesions. However, the ideal treatment strategy is poorly defined. We present a case of successful treatment of a large coronary artery aneurysm with a reverse saphenous interposition vein graft. This modality offers important benefits over other current surgical and percutaneous techniques and should be considered as an option for patients requiring treatment for coronary aneurysms.

Adult↗

Risk factors and outcomes after coronary reoperation in 739 elderly patients.

BACKGROUND: As second coronary artery bypass graft (CABG) operations are becoming more common in elderly patients, we conducted a retrospective analysis of risk factors for in-hospital and late outcome in patients aged 70 and over. METHODS: We reviewed records of 739 patients who underwent second CABG at age 70 or older at our institution between 1983 and 1993. Preoperative, operative, and postoperative variables were analyzed to identify predictors of in-hospital and long-term mortality. RESULTS: The mean age (+/- standard deviation) at reoperation was 74 +/- 3 years and the mean interval after primary operation was 130 +/- 55 months. In-hospital mortality was 7.6% (n = 56). Preoperative factors associated with increased in-hospital mortality were preoperative creatinine greater than 1.6 mg/dL (p < 0.001), emergency operation (p < 0.001), female sex (p = 0.012), moderate or severe left ventricular dysfunction (p = 0.049), and left main coronary disease (p = 0.045). In-hospital, actuarial survival was 75% at 5 years and 49% at 10 years. Cardiac event-free survival was 60% at 5 years and 27% at 10 years. The factors independently associated with increased late death were hematocrit (p = 0.046), diabetes (p = 0.011), peripheral vascular disease (p < 0.001), left ventricular function (p < 0.001), history of cancer (p = 0.016), preoperative nonsinus rhythm (p = 0.003), anticoagulation or antiplatelet therapy (p = 0.018), postoperative encephalopathy (p = 0.001), and postoperative stroke (p = 0.014). CONCLUSIONS: CABG reoperation can have excellent results for many elderly patients, but mortality is markedly higher when elderly patients have certain risk factors and comorbidities, alone or in combination. This information should be helpful in educating patients before they decide whether to choose reoperation.

Aged↗

Long-term effectiveness of operations for ascending aortic dissections.

OBJECTIVE: To evaluate long-term effectiveness of a strategy for managing the aortic root and distal aorta according to the pathology in ascending aortic dissection. METHODS: From 1978 to 1995, 208 patients underwent operations for acute (n = 135) and chronic (n = 73) ascending aortic dissection. Surgical strategies included valve resuspension with supracoronary aortic root repair and ascending aortic graft for normal sinuses and valve (n = 135), composite valve and ascending aortic graft for abnormal sinuses and valve (n = 47), and valve replacement and supracoronary ascending aortic graft for normal sinuses and abnormal valve (n = 26). Resection extended into the arch only if the intimal tear originated in or extended to the aortic arch (n = 31). RESULTS: Hospital mortality was 14%. Cardiogenic shock (P =.002) and concomitant coronary artery bypass grafting (P =.001) were associated with increased risk; use of circulatory arrest (P =.0003) decreased risk. Survival was 87%, 68%, and 52% at 30 days, 5 years, and 10 years, respectively. Advanced age, earlier date of operation, composite graft, and arch resection were associated with decreased survival; residual distal dissected aorta was not. Reoperation was required for 5 proximal and 8 distal problems. CONCLUSIONS: In both acute and chronic ascending aortic dissections, (1) circulatory arrest is associated with low early mortality; (2) with normal sinuses and valve, supracoronary repair of the dissected aortic root and valve resuspension is effective long term; and (3) residual distal dissected aorta does not decrease late survival and has a low risk of aneurysmal change and reoperation for at least 10 years.

Adult↗

Aortic valve replacement: is valve size important?

OBJECTIVE: We sought to determine whether aortic prosthesis size adversely influences survival after aortic valve replacement. METHODS: A total of 892 adults receiving a mechanical (n = 346), pericardial (n = 463), or allograft (n = 83) valve for aortic stenosis were observed for up to 20 years (mean, 5.0 +/- 3.9 years) after primary isolated aortic valve replacement. We used multivariable propensity scores to adjust for valve selection factors, multivariable hazard function analyses to identify risk factors for all-cause mortality, and bootstrap resampling to quantify the reliability of the results. RESULTS: Twenty-five percent of patients had indexed internal orifice areas of less than 1.5 cm(2)/m(2) and more than 2 SDs (Z-value) below predicted normal aortic valve size. Mechanical valve orifices were smaller (1.3 +/- 0. 29 cm(2)/m(2), Z = -2.2 +/- 1.16) than pericardial (1.9 +/- 0.36 cm(2)/m(2), Z = -0.40 +/- 1.01) or allograft valves (2.1 +/- 0.50, Z = 0.24 +/- 1.17). The overall survival was 98%, 96%, 86%, 69%, and 49% at 30 days and 1, 5, 10, and 15 years postoperatively. Univariably, survival was weakly and inversely related to manufacturer valve size (P =.16) and internal orifice diameter (P =. 2) but completely unrelated to indexed valve area (P =.6) or Z-value (P =.8). These, and univariable differences among valve types (P =. 004), were accounted for by different prevalences in patient risk factors and not by valve size or type per se. Bootstrap resampling indicated that these findings had a less than 15% chance of being incorrect. CONCLUSIONS: Survival after aortic valve replacement is strongly related to patient risk factors but appears not to be adversely affected by moderate patient-prosthesis mismatch (down to about 4 SDs below normal). Aortic root enlargement to accommodate a large prosthesis may be required in few situations.

Adolescent↗

Proteinuria is a key determinant of death in patients with diabetes after isolated coronary artery bypass grafting.

BACKGROUND: Proteinuria is a marker for underlying diabetic nephropathy and may be a surrogate marker for advanced atherosclerosis. It is unknown if proteinuria is a determinant of death in patients with diabetes after coronary artery bypass grafting. We hypothesized that diabetic patients with evidence of proteinuria would have increased mortality and clinical event rates after isolated coronary artery bypass grafting compared with nonproteinuric diabetic patients. METHODS AND RESULTS: We performed an observational of study of 905 diabetic patients with urinalysis and available follow-up data (nonproteinuria, n = 651; proteinuria, n = 254) after isolated coronary artery bypass grafting at the Cleveland Clinic Foundation between January 1989 and December 1992. The proteinuria group was further prospectively stratified into low-concentration (n = 225) and high-concentration (n = 29) groups. The end points of this study were all-cause mortality and the composite end point of death, nonfatal myocardial infarction, and need for repeat revascularization. The mean follow-up time was 66 months. The 5-year mortality rate for the nonproteinuria and proteinuria groups was 20.2% and 29.1% (P <.001), respectively. The 5-year rate of death, nonfatal myocardial infarction, and need for repeat revascularization for the nonproteinuria and proteinuria groups was 25.2% and 36.2% (P <.001), respectively. Significant multivariate predictors of 5-year mortality included age, not using a left internal mammary artery graft to the left anterior descending coronary artery, proteinuria, lower body weight, and increased creatinine level. CONCLUSIONS: Among diabetic patients, proteinuria appears to be an important predictor of death after isolated coronary artery bypass grafting.

Aged↗

Reduced survival in women after valve surgery for aortic regurgitation: effect of aortic enlargement and late aortic rupture.

OBJECTIVE: We sought to investigate the relationship of female sex, aortic pathology, and left ventricular function to outcome after an operation for aortic regurgitation. METHODS: One hundred nine women underwent aortic valve replacement (n = 92) or repair (n = 17) for pure aortic regurgitation between 1985 and 1996. Mean follow-up was 5.7 +/- 2.6 years. New York Heart Association functional class III-IV symptoms were present in 70 patients, whereas left ventricular function was normal in 60 patients. Ascending aortic diameter in 97% exceeded the 90th percentile for a size-matched healthy population. A concomitant aortic operation was performed by means of root replacement in 31 patients and by means of interposition graft in 28 patients. Of 50 patients undergoing isolated valve procedures, 19 had aortas of 4.0 cm or larger. RESULTS: At 5 and 10 years, survival was 78% and 44%, respectively. Fatal aortic rupture occurred in 13 patients, and 2 others underwent emergency operations for impending aortic rupture, for a total of 15 late aortic events. Freedom from aortic events was 87% and 76% at 5 and 10 years, respectively. Risk factors for aortic events were older age (P =.07) and increasing ascending aortic diameter indexed to body surface area (P =.03) in women who had not undergone replacement of the ascending aorta. Rupture location was at the ascending aorta in 71% without ascending replacement and the descending aorta in 62% with ascending grafts. CONCLUSION: In women, late survival after an operation for aortic regurgitation is importantly decreased by coexisting aortic pathology with subsequent aortic rupture. Aortic replacement at the time of a valve operation should be considered on the basis of indexed aortic size.

Aged↗