Continuous evolution of risk assessment methods for cardiac surgery and intervention

Trends, Predictors, and Outcomes of Stroke After Surgical Aortic Valve Replacement in the United States

BACKGROUND

Postoperative stroke is a devastating complication after aortic valve replacement (AVR). Our objective was to use a large national database to identify the incidence of and risk factors for stroke after AVR, as well as to determine incremental mortality, resource use, and cost of stroke.

METHODS

We identified 360,437 patients who underwent isolated surgical AVR between 1998 and 2011 from the National Inpatient Sample (NIH) database. Mean age was 66 ± 32 years. Multivariable regression and propensity matching were used to identify risk factors and the effect of stroke on outcomes. Patients were stratified according to the Elixhauser comorbidity score (ECS) into low- (0-5), medium- (6-15), and high-risk (16+) categories.

RESULTS

Stroke after AVR occurred in 5,092 (1.45%) patients. The incidence of stroke declined from 1.69% in 1999 to 0.94% in 2011 (p < 0.001). Increasing age and higher comorbidities were the main predictors of stroke (each p < 0.001). The highest-volume centers (>200 AVRs/y) had the lowest rate of stroke (1.2%). After multivariable adjustment, high-volume centers had lower odds of stroke in medium-risk (odds ratio [OR], 0.59; 95% confidence interval [CI], 0.37-0.94) and high-risk patients (OR, 0.39; 95% CI, 0.22-0.68) compared with the lowest-volume centers. For low-risk patients, volume was not associated with stroke. Patients who experienced stroke were hospitalized for 4 days longer, had an average of $10,496 higher costs, and had 2.74 (95% CI, 1.97-3.80) times higher odds of in-hospital mortality compared with those who did not experience stroke (all p < 0.001).

CONCLUSIONS

The incidence of stroke after AVR has decreased but remains a significant cause of morbidity in medium- and high-risk patients. Superior outcomes can be achieved in medium- to high-risk patients at high-volume centers.

Prophylactic stage 1 elephant trunk for moderately dilated descending aorta in patients with predominantly proximal disease

OBJECTIVE

Staged elephant trunk (ET) repair is a commonly performed procedure for extensive aortic disease. A significant proportion of patients with predominantly proximal aortic pathology often have in addition a moderately dilated descending aorta (<5 cm) that can progress over time. Objectives were to characterize patients, determine completion rate after prophylactic stage 1 ET, and assess outcomes.

METHODS

From 1992 to 2012, a total of 572 patients underwent stage 1 ET for degenerative aneurysm and dissection at Cleveland Clinic. Prophylactic stage 1 ET was performed in 117 (20.5%) who had predominantly proximal disease (5.5 ± 1 cm) with moderate dilation of the descending aorta (4 ± 0.6 cm). Aortic pathology included: aneurysm (n = 56 [48%]); chronic dissection (n = 41 [35%]); pseudoaneurysm (n = 9 [7.7%]); penetrating ulcer (n = 9 [7.7%]); and intramural hematoma (n = 2 [1.7%]). Other diagnoses included connective tissue disorder (12 [10%]); aortitis (20 [17%]); bicuspid aortic valve (9 [7.6%]); and previous type A dissection repair (27 [23%]).

RESULTS

Operative mortality was 0.8% (1 of 117). This patient suffered postoperative myocardial infarction and mesenteric ischemia, resulting in sepsis and death. Other complications included: stroke (n = 7 [6%]); tracheostomy (n = 6 [5%]); renal dialysis (n = 4 [3.3%]); and reoperation for bleeding (n = 7 [6%]). The mean follow-up time was 4 ± 3 years. Fifty-three (45%) patients completed the stage 2 ET (open: 20 [38%]; endovascular: 33 [62%]) at a median interval of 6 months (9 days-10 years). The mean descending diameter increased from 4.1 ± 0.6 cm to 5 ± 1 cm at the time of stage 2 completion. In 11 patients, stage 2 was performed for acute aortic events. Estimated survival at 1, 5, and 8 years was 94%, 88%, and 74%, respectively.

CONCLUSIONS

Prophylactic ET for moderately dilated descending aorta is an effective strategy for staged repair, especially in patients with chronic dissection, connective tissue disorder, and aortitis. In addition, this approach can be beneficial for emergency treatment of late distal aortic complications.