Aortic valve replacement with combined myocardial revascularisation

Comparison of Long-Term Outcomes of Patients Having Surgical Aortic Valve Replacement With Versus Without Simultaneous Coronary Artery Bypass Grafting

Coronary artery disease is a common co-morbidity of aortic stenosis. When needed, adding coronary artery bypass grafting (CABG) to surgical aortic valve replacement (SAVR) is the standard treatment method, but the impact of concomitant CABG on long-term outcomes is uncertain. We compared long-term outcomes of SAVR patients with and without CABG. Hospital survivors aged ≥50 years discharged after SAVR ± CABG in Finland between 2004 and 2014 (n = 6,870) were retrospectively studied using nationwide registries. Propensity score matching (1:1) was used to identify patients with comparable baseline features (n = 2,188 patient pairs, mean age 73 years). The end points were postoperative 10-year major adverse cardiovascular outcome (MACE), all-cause mortality, stroke, major bleeding, and myocardial infarction. Median follow-up was 6 years. Cumulative MACE rate (39.5% vs 35.6%; hazard ratio [HR] 1.04; p = 0.677) and mortality (32.7% vs 31.0%; HR 1.03; p = 0.729) after SAVR were comparable with or without CABG. Myocardial infarction was more common in patients with CABG (13.4% vs 6.9%; HR 1.47; p = 0.0495). Occurrence of stroke (15.1% vs 13.5%; p = 0.998) and major bleeding (20.0% vs 21.9%; p = 0.569) were comparable. There was no difference in gastrointestinal (8.1% vs 10.3%; p = 0.978) or intracranial bleeds (6.0% vs 5.5%; p = 0.794). The use of internal mammary artery in CABG did not have an impact on the results. In conclusion, matched patients with and without concomitant CABG had comparable long-term MACE, mortality, stroke, and major bleeding rates after SAVR. In conclusion, our results indicate that need for concomitant CABG has limited impact on long-term outcomes after initially successful SAVR.

Outcomes after aortic valve replacement for aortic valve stenosis, with or without concomitant coronary artery bypass grafting

OBJECTIVES

To assess the effects of concomitant coronary artery bypass grafting (CABG), we analyzed the outcomes after aortic valve replacement (AVR) for aortic stenosis (AS) with and without coronary artery bypass grafting (CABG) at our institution.

METHODS

Between 2002 and 2014, 605 consecutive patients underwent AVR for AS. Of these, the 275 who received isolated AVR (Group A) and the 122 who received both AVR and CABG (Group AC) patients were enrolled, after the exclusion of 8 patients who underwent reoperation and 200 who received other concomitant surgery. AVR and all bypass anastomoses were performed under intermittent retrograde cold blood cardioplegia. Multivariate analysis was used to assess any association of concomitant CABG with morbidity and mortality. Kaplan-Meier analysis was used to assess all-cause mortality.

RESULTS

No significant difference in 30-day mortality was found between Group A and Group AC (1.5% vs. 0.8%, P = 1.000). Nor did post-discharge survival differ significantly between the two groups (P = 0.20). Likewise, multivariate analysis showed that concomitant CABG was not associated with significantly greater in-hospital or mid-term mortality. Operative morbidities were comparable between the two groups, in terms of stroke (1.8% vs. 3.3%, P = 0.466), prolonged ventilation (4.0% vs. 5.5%, P = 0.565), deep sternal infection (1.8% vs. 3.3%, P = 0.466), and acute renal failure (0.4% vs. 1.6% P = 0.176).

CONCLUSIONS

Concomitant CABG at the time of AVR was performed without increasing early- or mid-term mortality. This absence of increased risk deserves consideration when choosing between different treatment strategies.

Prediction of coronary artery disease in patients undergoing operations for rheumatic aortic valve disease

BACKGROUND

We sought to develop and validate a logistic model and a simple score system for prediction of significant coronary artery disease (CAD) in patients undergoing operations for rheumatic aortic valve disease.

HYPOTHESIS

The simple score model we established based on the logistic model was efficient and practical.

METHODS

A total of 669 rheumatic patients (mean age 51 ± 9 years), who underwent routine coronary angiography (CAG) before aortic valve surgery between 1998 and 2010, were analyzed. A bootstrap-validated logistic regression model on the basis of clinical risk factors was developed to identify low-risk (≤5%) patients, from which an additive model was derived. Receiver operating characteristic (ROC) curves were used to compare discrimination, and precision was quantified by the Hosmer-Lemeshow statistic. Significant coronary atherosclerosis was defined as 50% or more luminal narrowing in 1 or more major epicardial vessels determined by means of coronary angiography.

RESULTS

Eighty-eight (13.2%) patients had significant coronary atherosclerosis. Independent predictors of CAD include age, angina, diabetes mellitus, and hypertension. A total of 325 patients were designated as low risk according to the bootstrap logistic regression and additive models. Of these patients, only 4 (1.2%) had single-vessel disease, and none had high-risk CAD (ie, left main trunk, proximal left anterior descending, or multivessel disease). The bootstrap logistic regression and additive models show good discrimination, with an area under the ROC curve of 0.948 and 0.942, respectively.

CONCLUSIONS

Our logistic regression model can reliably estimate the prevalence of significant CAD in rheumatic patients undergoing aortic valve operation, while the additive simple score system could reliably identify the low-risk patients in whom routine preoperative angiography might be safely avoided.

Aortic Valve Replacement for Aortic Stenosis and Concomitant Coronary Artery Bypass: Long-term Outcomes and Predictors of Mortality

Background

We evaluated the surgical results and predictors of long-term survival in patients who underwent coronary artery bypass grafting (CABG) at the time of an aortic valve replacement (AVR) due to aortic stenosis.

Materials and Methods

Between January 1990 and December 2009, 183 consecutive patients underwent CABG and concomitant aortic valve replacement for aortic stenosis. The mean follow-up period was 59.8±3.3 months and follow-up was possible in 98.3% of cases. Predictors of mortality were determined by Cox regression analysis.

Results

There were 5 (2.7%) in-hospital deaths. Follow-up of the in-hospital survivors documented late survival rates of 91.5%, 74.8%, and 59.6% at 1, 5, and 10 postoperative years, respectively. Age (p<0.001), a glomerular filtration rate (GFR) less than 60 mL/min (p=0.006), and left ventricular (LV) mass (p<0.001) were significant predictors of mortality in the multivariate analysis.

Conclusion

The surgical results and long-term survival of aortic valve replacement with concomitant CABG in patients with aortic stenosis and coronary artery disease were acceptable. Age, a GFR less than 60 mL/min, and LV mass were significant predictors of mortality.

Aortic Valve Replacement and Concomitant Coronary Artery Bypass: Assessing the Impact of Multiple Grafts

BACKGROUND

The impact of multivessel coronary artery disease and multivessel coronary artery bypass grafting on outcomes after combined aortic valve replacement and coronary artery bypass grafting (AVR-CABG) has not been sufficiently evaluated.

METHODS

We retrospectively reviewed all patients who underwent AVR-CABG at our institution between January 2000 and December 2004. Patients with any previous or concomitant procedures were excluded. The Kaplan-Meier method was used to calculate survival and freedom from postoperative repeat revascularization. Predictors of mortality were determined by Cox regression analysis.

RESULTS

The study cohort consisted of 233 AVR-CABG patients. Mean follow-up was 2.2 +/- 1.7 years with one patient lost to follow-up. Preoperative clinical characteristics were well-matched between patients who received one (n = 86), two (n = 81), or three or four (n = 66) bypass grafts. Operative mortality was 9.3%, 11.1%, and 7.6%, respectively (p = 0.76). Patients in all groups demonstrated significant improvement in New York Heart Association (NYHA) status (p < 0.01). Freedom from postoperative repeat revascularization for all patients after five years was 96.8% and did not differ among groups (p = 0.93). Five-year survival for each group was 63.6%, 72.4%, and 63.9%, respectively (p = 0.91). Emergent operation, ejection fraction less than 0.30, operative age greater than 65 years, NYHA class III/IV, and chronic obstructive pulmonary disease were significant predictors of mortality. The number of stenosed vessels, the number of bypass grafts, incomplete revascularization, and the presence of aortic stenosis or aortic insufficiency did not predict mortality.

CONCLUSIONS

For patients undergoing AVR-CABG, the number of bypass grafts does not adversely affect survival. Rather, a patient's preoperative risk factors are a better predictor of outcome.

Aortic valve surgery following previous coronary artery bypass grafting. Impact of calcification and leaflet movement

We reviewed the reports of 27 patients who had an aortic valve replacement after previous coronary artery bypass grafting. The aortic valve disease -- mainly aortic stenosis -- showed a rapid rate of progression. In the time interval between coronary artery bypass grafting and aortic valve replacement of 4.6+/-2.2 years the peak-to-peak pressure gradient of the aortic valve rose from 20.2+/-14.3 to 63.0+/-22.7 mmHg. As there is a great interest to identify the patients with a high risk of a rapid progression because of a high mortality of an aortic valve replacement as the second cardiac operation following a coronary artery bypass grafting we also reviewed the cardiac catheterisation films and found a high incidence of calcification and impaired aortic valve motion (81.5% of the patients had already calcified aortic valves and 81.5% had a impaired valve motion) at the time of coronary artery bypass grafting. We concluded that if a patient has to be operated for coronary artery disease an aortic valve replacement should be considered not only according to hemodynamic criteria but also when the aortic valve is calcified or its leaflets' motion is impaired.

Use of transesophageal echocardiography to predict significant coronary artery disease in aortic stenosis

STUDY OBJECTIVES

This study was conducted to examine if the use of multiplane transesophageal echocardiography (TEE) could predict the absence or the presence of significant coronary artery disease (CAD) in patients with aortic stenosis.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENTS

Clinical, angiographic features and TEE findings were prospectively analyzed in 132 consecutive patients with aortic stenosis.

MEASUREMENTS AND RESULTS

In 63 patients with significant CAD, 57 had thoracic aortic plaque on TEE studies. In contrast, aortic plaque existed in only 19 of the remaining 69 patients with normal or mildly abnormal coronary arteries. Therefore, the presence of aortic plaque on the TEE identified significant CAD with a sensitivity of 90.5%, a specificity of 72.5%, and with positive and negative predictive values of 75.0% and 89.3%, respectively. There was a significant relation between the severity of thoracic aortic atherosclerosis and the severity of CAD (p<0.0001). Multivariate logistic regression analysis revealed that aortic plaque, angina, and age were independent predictors of CAD. Aortic plaque was the most significant independent predictor.

CONCLUSION

This prospective study indicates that TEE examination of thoracic atherosclerotic plaque is a powerful predictor of absence of significant CAD in patients with aortic stenosis.

Early and late mortality of patients undergoing aortic valve replacement after previous coronary artery bypass graft surgery

BACKGROUND

In a small number of patients who undergo coronary artery bypass graft surgery (CABG), a hemodynamically significant aortic valve lesion requiring aortic valve replacement (AVR) develops as they grow older. In a limited number of studies in small patient groups, high mortality has been shown in patients undergoing AVR after CABG. We undertook this study to determine the mortality risk factors for patients who undergo AVR after CABG procedures.

METHODS AND RESULTS

The outcome of 104 patients treated at our institution between January 1983 and December 1993 was retrospectively reviewed. The initial surgery was CABG in all patients. The patient population included 86 men (83%) and 18 women (17%); their mean age was 67 years. Overall, 70% of patients had congestive heart failure, and 96% had multivessel coronary artery disease. The diagnosis was aortic stenosis in 68% of patients, aortic insufficiency in 16%, and combined aortic stenosis and aortic insufficiency in 16%. Postoperative complications included worsening congestive heart failure (35%), perioperative myocardial infarction (13%), and bleeding (28%). The early mortality was 14%, and the late mortality was 17% (mean follow-up, 35 months). The risk factors for early mortality were number of diseased vessels (P = .028), renal failure (0.000), and prior myocardial infarction (P = .028). A perioperative predictor of early mortality was cardiopulmonary bypass time (P = .000). The risk factors for late mortality included preoperative diabetes mellitus (P = .007), postoperative acute respiratory distress syndrome (P = .011), and ventricular arrhythmias (P = .0001). The survival at 1, 5, and 10 years was 96%, 75%, and 49%, respectively.

CONCLUSIONS

Risk factors were identified for early and late mortality in patients undergoing AVR after previous CABG. Although early morbidity and mortality were high, the longterm outcome of the survivors was favorable.

Dipyridamole thallium-201 single-photon emission tomography in aortic stenosis: gender differences

Dipyridamole single-photon emission tomography (SPET) is used for the detection of coronary artery disease (CAD) and the method has also been applied in patients with aortic stenosis. This study was undertaken to establish the gender-specific normal limits of thallium-201 distribution in patients with aortic stenosis and to apply these normal limits in a larger group of patients with aortic stenosis to obtain the sensitivity and specificity for coexisting CAD. A low-dose dipyridamole protocol was used (0.56 mg/kg during 4 min). Thallium was injected 2 min later and tomographic imaging was performed. Following image reconstruction a basal, a midventricular and an apical short-axis slice were selected. The highest activity in each 6 degree segment was normalised to the maximal activity of each slice. The normal uptake for patients with aortic stenosis was obtained from ten men and ten women with aortic stenosis and a normal coronary angiography. Eighty-nine patients were prospectively evaluated. An area reduction of at least 75% in a coronary artery was considered to be a significant coronary lesion and was found in 57 (64%) patients. With gender-specific curves (-2.5 SD) sensitivity for detecting CAD was 100% and specificity was 75% in men, while sensitivity was 61% and specificity 64% in women. It is concluded that the gender-specific normal distribution of 201Tl uptake in patients with aortic stenosis, using dipyridamole SPET, yields a high sensitivity and specificity for coronary artery lesions in men but a lower sensitivity and specificity in women with aortic stenosis.

Exclusion of coronary artery disease by exercise thallium-201 tomography in patients with aortic valve stenosis

In many patients with valvular aortic stenosis (AS), management decisions may be possible without invasive studies if coexistent coronary artery disease (CAD) can be ruled out noninvasively. The use of thallium-201 single-photon emission computed tomography to the exclusion of CAD was studied in 44 patients aged 41 to 78 years with AS. In addition to cardiac catheterization and selective coronary angiography, patients underwent a cardiac ultrasound study and thallium-201 myocardial perfusion imaging at rest and after bicycle ergometer exercise. Two thirds of the patients had critical AS (valve area index less than or equal to 0.5 cm2/m2) but none had left ventricular systolic dysfunction. Twenty-one patients had angiographically significant CAD (greater than or equal to 50% diameter stenosis in greater than or equal to 1 coronary artery), whereas 23 had either a fully normal angiogram (n = 17) or mild (less than 50%) stenoses (n = 6). Each patient with significant CAD had an abnormal thallium-201 tomogram, either a strictly segmental perfusion defect (n = 19), or a patchy nonsegmental abnormality (n = 2); however, 10 of 23 patients free of significant CAD had similar results. Thus, the sensitivity and specificity of an abnormal scintigram were 100 and 57%, respectively. If only segmental perfusion defects typical of CAD had been considered abnormal, then the sensitivity of the test would have been 90% and the specificity 70%. Patients with false abnormal scintigrams had more severe AS and more angiographically nonsignificant CAD than those with true normal findings.(ABSTRACT TRUNCATED AT 250 WORDS)

Early results of aortic valve replacement with or without concomitant coronary artery bypass grafting

Early results of aortic valve replacement were reviewed in 962 unselected patients, 659 without concomitant coronary bypass surgery (AVR group) and 303 with combined valve replacement and coronary artery bypass grafting (AVR + CABG). The early (less than 30-day) mortality was 4.6% in the AVR, and 5.9% in the AVR + CABG group. Multivariate analysis showed coronary artery stenoses and NYHA functional class to be independent predictors of early mortality in the AVR group, and the number of distal anastomoses as the strongest predictor in AVR + CABG. The incidence of peroperative technical complications in the cases with fatal outcome was 27% in the AVR and 6% in the AVR + CABG group. The incidence of myocardial injury (new Q wave or evidence of increased enzyme leakage) was 11% in AVR and 21% in AVR + CABG. Independent predictors of postoperative myocardial injury were aortic cross-clamp time, year of surgery, coronary artery stenoses and NYHA class in AVR and aortic cross-clamp time and year of surgery in AVR + CABG. The study suggests that coronary artery disease increases risk in aortic valve replacement with or without CABG. Replacement should be undertaken before endstage of the disease (NYHA IV), with CABG if significant coronary disease is present, and in multivessel disease the number of distal anastomoses should be restricted in order to shorten aortic cross-clamp time.

Decision analysis in clinical cardiology: when is coronary angiography required in aortic stenosis?

Decision analysis offers a reproducible, explicit approach to complex clinical decisions. It consists of developing a model, typically a decision tree, that separates choices from chances and that specifies and assigns relative values to outcomes. Sensitivity analysis allows exploration of alternative assumptions. Cost-effectiveness analysis shows the relation between dollars spent and improved health outcomes achieved. In a tutorial format, this approach is applied to the decision whether to perform coronary angiography in a patient who requires aortic valve replacement for critical aortic stenosis.