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Bruce W Lytle

Publications and source records attributed to Bruce W Lytle.

At least 37 records · Page 2Linked to original sources
PubMed2005

Evaluation of left ventricular outflow tract area after septal reduction in obstructive hypertrophic cardiomyopathy: a real-time 3-dimensional echocardiographic study.

BACKGROUND: The comparative impact of percutaneous alcohol septal reduction (ASR) and surgical myectomy on the left ventricular outflow tract (LVOT) area in patients with obstructive hypertrophic cardiomyopathy (HC) is not well defined. Real-time 3-dimensional echocardiography (RT3DE) provides accurate information about the LVOT geometry and shape. We aimed to analyze the change in LVOT area after septal reduction interventions in patients with obstructive HC using RT3DE. METHODS: Thirty-one HC patients (mean age 53 +/- 17 years) undergoing ASR (n = 14) or myectomy (n = 17) were studied at baseline and during follow-up with RT3DE. LVOT area was measured after observing the LVOT in the 3D space as the smallest area during midsystole. LVOT pressure gradients were determined by conventional continuous wave Doppler. RESULTS: Overall, LVOT area increased from 0.86 +/- 0.20 to 2.50 +/- 0.88 cm2 (P < .01), and the resting LVOT pressure gradient decreased from 64 +/- 41 to 16 +/- 10 mm Hg (P < .01) after a median follow-up of 3 months after intervention (range 1-24 months). A similar significant decrease in LVOT pressure gradients was seen in myectomy and ASR groups (from 62 +/- 39 to 12 +/- 5 mm Hg and from 67 +/- 43 to 21 +/- 14 mm Hg, respectively, P < .01 in between each group, and P = NS between both groups). However, the increase in LVOT area was greater in myectomy than in ASR group (from 0.81 +/- 0.22 to 2.90 +/- 0.64 cm2 and 0.93 +/- to 0.16 to 2.02 +/- 0.92 cm2, respectively, P < .01 between both groups). CONCLUSION: RT3DE demonstrated an effective increase in LVOT area after both ASR and myectomy. This technique may be useful for assessing the results of septal reduction in patients with obstructive HC.

Adolescent↗
PubMed2005

Comparison of saphenous vein and internal thoracic artery graft patency by coronary system.

BACKGROUND: We sought to compare saphenous vein and internal thoracic artery graft patency by coronary system. METHODS: From 1972 to 1999, 50,278 patients underwent primary coronary surgery; subsequently, 4,333 had angiography of 2,121 internal thoracic artery and 8,733 saphenous vein grafts. Longitudinal analysis was used to model graft occlusion and identify risk factors. Using the model, patency was calculated twice for each graft and compared first as if an internal thoracic artery, and second as if a saphenous vein, were used. RESULTS: Unadjusted 1-, 5-, and 10-year patency was 93%, 88%, and 90% for internal thoracic arteries and 78%, 65%, and 57% for saphenous veins. At 10 years, internal thoracic arteries were more likely than saphenous veins to be patent to left anterior descending in 99.1% of cases, to diagonals in 98.3%, to circumflex in 98.3%, to posterior descending artery in 98.5%, and to right coronary arteries in 82.5%. For right coronary arteries, saphenous vein patency was equivalent to or better than internal thoracic artery patency early after surgery. However, by 10 years, internal thoracic artery patency was better in right coronary arteries with 70% stenosis or greater. At all times after surgery and all levels of clinically important coronary stenosis, internal thoracic artery patency surpassed saphenous vein patency in grafts to the left anterior descending, diagonal, circumflex, and posterior descending arteries. CONCLUSIONS: Internal thoracic arteries demonstrate better patency than saphenous veins except when grafting moderately stenosed right coronary arteries. When bypassing right coronary arteries with less than 70% stenosis, saphenous veins may be a better choice.

Coronary Angiography↗
PubMed2005

Ischemic versus degenerative mitral regurgitation: does etiology affect survival?

BACKGROUND: Ischemic mitral regurgitation (MR) is associated with poor survival and degenerative MR with excellent survival. We hypothesized that in some patients with degenerative MR requiring concomitant coronary artery bypass grafting (CABG), ischemic disease would dominate prognosis, resulting in survival as poor as in patients with ischemic MR. Thus, we (1) determined survival impact of etiology (degenerative vs ischemic) after combined mitral valve repair and CABG and (2) explored survival differences within etiology groups. METHODS: From 1985 to 2003, 710 patients underwent mitral valve repair for degenerative MR and concomitant CABG (two diseases); 400 patients had mitral annuloplasty and CABG for functional ischemic MR (one disease). Patients were propensity-matched on demography, symptoms, comorbidities, coronary artery disease, and left ventricular function. Survival was compared between matched groups and within groups. RESULTS: Compared with patients with degenerative MR, those with ischemic MR had more extensive coronary artery disease, worse ventricular function, more comorbidities, and more symptoms (p < 0.05). Unadjusted 5-year survivals were 64% and 82% for patients with ischemic and degenerative MR, respectively. However, 123 ischemic and degenerative MR matched pairs had equivalently poor 5-year survival (p > 0.9), 66% and 65%, respectively. Among patients with degenerative MR, survival varied widely, depending largely on ischemic burden and extent of left ventricular dysfunction. CONCLUSIONS: The large survival discrepancy between patients with ischemic and degenerative MR is attributable to differences in patient profile, particularly extent of ischemic disease and left ventricular dysfunction. Thus, ischemic and degenerative MR patients with equivalent characteristics have equivalently poor survival.

Aged↗
PubMed2005

Is reoperation still a risk factor in coronary artery bypass surgery?

BACKGROUND: Hospital mortality for reoperative coronary artery bypass grafting (CABG) is approaching that of primary CABG. This raises two questions: (1) has experience neutralized the risk of reoperation attributable to its greater difficulty, or (2) has experience neutralized the risk attributable to the higher-risk profile of reoperative patients?. METHODS: From 1990 to 2003, 21,568 CABG procedures were performed, of which 4,518 (21%) were reoperations: 3,919 first, 552 second, 43 third, 3 fourth, and 1 fifth. Reoperative patients had a higher-risk profile than primary patients, with more vascular disease, left ventricular dysfunction, and coronary artery disease (all p < 0.0001). Logistic regression was used to identify factors associated with hospital death and to develop a propensity score for reoperation, which was used to (1) adjust multivariable analyses of death and (2) compare outcomes in matched patients. RESULTS: Hospital mortality was 4.3% (168 of 3,919) for first reoperation, 5.1% (28 of 552) for second, and 6.4% (3 of 47) for third or more, compared with 1.5% (263 of 17,050) for primary operations. Risk of both primary and reoperative CABG decreased with experience (p > 0.0002); however, reoperative risk fell markedly in the mid-1990s. In both the overall and matched-pairs analyses, reoperation was a risk factor before 1997 (p < or = 0.008), but not after (p = 0.2). Reoperation within 1 year of previous CABG increased risk (p < 0.0001). Risk attributable to left ventricular dysfunction decreased with experience (p = 0.05). CONCLUSIONS: Hospital mortality for reoperative CABG has been consistently higher than for primary operation, but this difference has narrowed considerably. Patient characteristics, not reoperation itself, now have greater influence.

Aged↗
PubMed2004

Usefulness of real-time three-dimensional echocardiography for evaluation of myectomy in patients with hypertrophic cardiomyopathy.

Real-time 3-dimensional echocardiography was performed in 10 patients with obstructive hypertrophic cardiomyopathy (HC) before and after myectomy and in 6 controls. The exact location of systolic anterior motion of the mitral leaflet was shown in all patients with HC with a predominant involvement of the medial portion in 4 patients and the middle portion in 6 patients. The smallest area of the left ventricular outflow tract was significantly smaller in patients with HC than in controls (1.4 +/- 0.7 vs 5.1 +/- 1.2 cm(2), p <0.01), significantly increased after myectomy (4.8 +/- 1.8 cm2, p <0.01) and was associated with a reduction of the pressure gradient at rest from 63 +/- 41 to 15 +/- 5 mm Hg (p <0.01).

Adult↗
PubMed2004

Propensity analysis of long-term survival after surgical or percutaneous revascularization in patients with multivessel coronary artery disease and high-risk features.

BACKGROUND: Although most randomized clinical trials have suggested that long-term survival rates after percutaneous coronary intervention (PCI) or surgical multivessel coronary revascularization (CABG) are equivalent, some post hoc analyses in high-risk groups and adjustment for severity of coronary disease have suggested higher mortality after PCI. METHODS AND RESULTS: We studied 6033 consecutive patients who underwent revascularization in the late 1990s. PCI was performed in 872 patients; 5161 underwent CABG. Half the patients had significant left ventricular dysfunction or diabetes. Propensity analysis to predict the probability of undergoing PCI according to 22 variables and their interactions was used. The C-statistic for this model was 0.90, indicating excellent discrimination between treatments. There were 931 deaths during 5 years of follow-up. The 1- and 5-year unadjusted mortality rates were 5% and 16% for PCI and 4% and 14% for CABG (unadjusted hazard ratio, 1.13; 95% CI, 1.0 to 1.4; P=0.07). PCI was associated with an increased risk of death (propensity-adjusted hazard ratio, 2.3; 95% CI, 1.9 to 2.9; P<0.0001). This difference was observed across all categories of propensity for PCI and in patients with diabetes or left ventricular dysfunction. Other independent predictors of mortality (P< or =0.01 for all) were renal dysfunction, age, diabetes mellitus, chronic lung disease, peripheral vascular disease, left main trunk stenosis, and extent of coronary disease (Duke angiographic score). CONCLUSIONS: In patients with multivessel coronary artery disease and many high-risk characteristics, CABG was associated with better survival than PCI after adjustment for risk profile.

Aged↗
PubMed2004

Constrictive pericarditis: etiology and cause-specific survival after pericardiectomy.

OBJECTIVES: We sought to determine the association of etiology of constrictive pericarditis (CP), pericardial calcification (CA), and other clinical variables with long-term survival after pericardiectomy. BACKGROUND: Constrictive pericarditis is the result of a spectrum of primary cardiac and noncardiac conditions. Few data exist on the cause-specific survival after pericardiectomy. The impact of CA on survival is unclear. METHODS: A total of 163 patients who underwent pericardiectomy for CP over a 24-year period at a single surgical center were studied. Constrictive pericarditis was confirmed by the surgical report. Vital status was obtained from the Social Security Death Index. RESULTS: Etiology of CP was idiopathic in 75 patients (46%), prior cardiac surgery in 60 patients (37%), radiation treatment in 15 patients (9%), and miscellaneous in 13 patients (8%). Median follow-up among survivors was 6.9 years (range 0.8 to 24.5 years), during which time there were 61 deaths. Perioperative mortality was 6%. Idiopathic CP had the best prognosis (7-year Kaplan-Meier survival: 88%, 95% confidence interval [CI] 76% to 94%) followed by postsurgical (66%, 95% CI 52% to 78%) and postradiation CP (27%, 95% CI 9% to 58%). In bootstrap-validated proportional hazards analyses, predictors of poor overall survival were prior radiation, worse renal function, higher pulmonary artery systolic pressure (PAP), abnormal left ventricular (LV) systolic function, lower serum sodium level, and older age. Pericardial calcification had no impact on survival. CONCLUSIONS: Long-term survival after pericardiectomy for CP is related to underlying etiology, LV systolic function, renal function, serum sodium, and PAP. The relatively good survival with idiopathic CP emphasizes the safety of pericardiectomy in this subgroup.

Adult↗
PubMed2004

Conduction system abnormalities in patients with obstructive hypertrophic cardiomyopathy following septal reduction interventions.

We observed the impact of percutaneous transluminal septal myocardial ablation (PTSMA) and myectomy on the conduction system in patients with obstructive hypertrophic cardiomyopathy (HC). Septal reduction intervention is capable of eliminating the left ventricular outflow tract obstruction in patients with obstructive HC; however, conduction system abnormalities are frequent consequences of these procedures. A standard 12-lead electrocardiogram and Doppler echocardiogram were obtained in 204 patients who underwent PTSMA (n = 70) or myectomy (n = 134) before and at average of 3 months after intervention. Of 146 patients who had normal conduction systems before intervention, the duration of the QRS complex was significantly prolonged from 98 +/- 15 to 130 +/- 25 ms (p <0.0001), with right bundle branch block (RBBB) developing in 62% patients after PTSMA, and from 100 +/- 13 to 154 +/- 20 ms (p <0.0001), with left bundle branch block (LBBB) developing in 93% patients after myectomy. No significant difference in the QRS duration was found in the remaining 58 patients who had preexisting conduction abnormalities after intervention. In 174 patients without a preexisting permanent pacemaker, a pacemaker was implanted in 22% versus 13% of patients who underwent PTSMA (overall and without preexisting conduction block, respectively) and 10% versus 2% of patients with myectomy. The duration of baseline QRS was an independent predictor for the requirement of a permanent pacemaker (p <0.0001). Thus, RBBB often develops after PTSMA and LBBB is very frequently produced by myectomy. A possible requirement of a permanent pacemaker should always be considered before intervention when patients have preexisting RBBB or LBBB.

Bundle-Branch Block↗
PubMed2004

Acute dissection of the descending aorta: noncommunicating versus communicating forms.

BACKGROUND: Noncommunicating dissecting intramural hematoma is an aortic dissection variant, characterized by absent flow within the false lumen. Noncommunicating dissecting intramural hematoma is thought to be more stable than communicating dissection when beginning in the descending aorta. This study assessed clinical characteristics, anatomic characteristics, and 1-year outcomes in acute descending noncommunicating dissecting intramural hematoma versus communicating dissection. METHODS: Retrospective database review identified patients who underwent magnetic resonance or computed tomography imaging revealing acute descending noncommunicating dissecting intramural hematoma or communicating dissection. Comparisons of clinical and anatomic characteristics and 1-year outcomes were performed. RESULTS: Twenty-four noncommunicating dissecting intramural hematoma and 36 communicating dissection cases were identified. Patients with noncommunicating dissecting intramural hematoma were older (68.5 +/- 8.8 versus 61.8 +/- 11.6 years; p < 0.05). Although noncommunicating dissecting intramural hematoma often showed abdominal aorta extension (50%), the infrarenal level was spared. Communicating dissection characteristically extended beyond the diaphragm (89%), including into the infrarenal aorta (28%). There was no significant difference in rates of adverse clinical events for noncommunicating dissecting intramural hematoma versus communicating dissection (13% versus 30%; 0.10 > p > 0.05). By follow-up imaging (87% of population), aortic deterioration was more frequent in noncommunicating dissecting intramural hematoma versus communicating dissection cases (60% versus 15%; p < 0.005). CONCLUSIONS: Acute descending noncommunicating dissecting intramural hematoma and communicating dissection represent two variants, with differing clinical and anatomic characteristics, but comparable levels of 1-year morbidity.

Acute Disease↗
PubMed2004

Cannulation of the axillary artery with a side graft reduces morbidity.

BACKGROUND: The axillary artery is our preferred arterial cannulation site when the ascending aorta cannot be cannulated. Previously, we cannulated the artery directly; now we use a side graft. The purposes of this study were to (1) investigate cannulation-related morbidity and (2) determine whether use of a side graft reduces it. METHODS: From January 1993 to January 2001, 392 patients underwent 399 axillary artery cannulations. Indications included calcified ascending aorta (129, 32%), ascending aortic aneurysm (115, 29%), type I aortic dissection (85, 21%), cardiac reoperation (70, 18%), and calcified femoral artery (26, 6%). The axillary artery was cannulated directly in 212 (53%) and with a side graft in 187 (47%). Comparisons of cannulation-related morbidity between the direct cannulation and side graft groups were made overall and after both adjusting and matching for propensity score. RESULTS: Cannulation-related morbidity was infrequent, with brachial plexus injury in 7 (1.8%), axillary artery damage in 7 (1.8%), aortic dissection in 3 (0.8%), and arm ischemia in 3 (0.8%). Only 4 of 187 (2.1%) occurred in the side graft group, versus 16 of 212 (7.0%) with direct cannulation (p = 0.03). After propensity adjustment, the odds ratio for reduction of risk of cannulation-related morbidity with use of a side graft was 0.15 (p = 0.002). CONCLUSIONS: Use of the axillary artery as inflow for cardiopulmonary bypass is associated with low morbidity. However, cannulation with a side graft was associated with less cannulation-related morbidity than direct cannulation. Routine use of a side graft is recommended whenever axillary artery cannulation is indicated.

Adolescent↗
PubMed2004

Does preoperative atrial fibrillation reduce survival after coronary artery bypass grafting?

BACKGROUND: Preoperative atrial fibrillation has been identified as a risk factor for reduced long-term survival after coronary artery bypass grafting. This study sought to determine whether atrial fibrillation is merely a marker for high-risk patients or an independent risk factor for time-related mortality. METHODS: From 1972 to 2000, 46,984 patients underwent primary isolated coronary artery bypass grafting; 451 (0.96% prevalence) had electrocardiogram-documented preoperative atrial fibrillation (n = 411) or flutter (n = 40). Characteristics of patients with and without atrial fibrillation were contrasted by multivariable logistic regression to form a propensity score. With this, comparable groups with and without atrial fibrillation were formed by pairwise propensity-matching to assess survival. RESULTS: Patients with preoperative atrial fibrillation were older (67 +/- 9.0 versus 59 +/- 9.8 years, p < 0.0001), had more left ventricular dysfunction (66% versus 52%, p < 0.0001) and hypertension (73% versus 59%, p < 0.0001), but less severe angina (39% moderate or severe versus 49%, p < 0.0001). Many of these factors are themselves predictors of increased time-related mortality. In propensity-matched patients, survival at 30 days and at 5 and 10 years for patients with versus without atrial fibrillation was 97% versus 99%, 68% versus 85%, and 42% versus 66%, respectively, a survival difference at 10 years of 24%. Median survival in patients with atrial fibrillation was 8.7 years versus 14 years for those without it. CONCLUSIONS: Atrial fibrillation in patients undergoing coronary artery bypass grafting is a marker for high-risk patients; in addition, atrial fibrillation itself substantially reduces long-term survival. Thus, if patients in atrial fibrillation require surgical revascularization, it is appropriate to consider performing a concomitant surgical ablation procedure.

Aged↗
PubMed2004

Redo-aortic valve replacement after previous bilateral internal thoracic artery bypass grafting.

BACKGROUND: Aortic valve replacement (AVR) after coronary artery bypass using bilateral internal thoracic arteries (ITAs) is a challenge. Management of these patent grafts and myocardial protection are important issues. Moreover the risk and outcome of these complex operations have not been clearly defined. METHODS: Eighteen consecutive patients (all male) who exhibited previous bilateral ITA grafts underwent subsequent AVR surgery from 1990-2001 at the Cleveland Clinic Foundation. Their medical records were retrospectively analyzed. RESULTS: At the time of reoperation, the mean age of the patients was 67 +/- 6.4 years and 33 out of 36 (92%) ITAs were patent. The interval between previous coronary bypass and aortic valve surgery was 10.3 +/- 5.3 years. All patients underwent redo-median sternotomy with aortic cannulation in 12 patients (67%) and femoral or axillary artery cannulation in 6 patients (33%). The patent ITAs were clamped during aortic cross-clamping in 15 patients. In 3 patients the ITAs were not dissected. These 3 patients underwent deep hypothermic arrest for myocardial protection. Concomitant coronary revascularization was performed in 8 patients (44%). There were no hospital deaths. One stroke occurred but there were no other major complications. Average intubation time was 23.1 +/- 27.1 hours, intensive care unit stay was 2.3 +/- 3.1 days, and postoperative hospital stay was 10.3 +/- 7.6 days. CONCLUSIONS: Reoperative aortic valve surgery in the patients with patent bilateral ITA grafts can be performed safely.

Aged↗