Faculty Bibliography
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143
Canadian Cardiovascular Society/Canadian Society of Cardiac Surgeons/Canadian Society for Vascular Surgery Joint Position Statement on Open and Endovascular Surgery for Thoracic Aortic Disease
In 2014, the Canadian Cardiovascular Society (CCS) published a position statement on the management of thoracic aortic disease addressing size thresholds for surgery, imaging modalities, medical therapy, and genetics. It did not address issues related to surgical intervention. This joint Position Statement on behalf of the CCS, Canadian Society of Cardiac Surgeons, and the Canadian Society for Vascular Surgery provides recommendations about thoracic aortic disease interventions, including: aortic valve repair, perfusion strategies for arch repair, extended arch hybrid reconstruction for acute type A dissection, endovascular management of arch and descending aortic aneurysms, and type B dissection. The position statement is constructed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and has been approved by the primary panel, an international secondary panel, and the CCS Guidelines Committee. Advent of endovascular technology has improved aortic surgery safety and extended the indications of minimally invasive thoracic aortic surgery. The combination of safer open surgery with endovascular treatment has improved patient outcomes in this rapidly evolving subspecialty field of cardiovascular surgery.
PMID: 27233892
ISSN: 1916-7075
CID: 5450822
Two-Year Outcomes of Surgical Treatment of Moderate Ischemic Mitral Regurgitation
BACKGROUND:In a trial comparing coronary-artery bypass grafting (CABG) alone with CABG plus mitral-valve repair in patients with moderate ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI) or survival after 1 year. Concomitant mitral-valve repair was associated with a reduced prevalence of moderate or severe mitral regurgitation, but patients had more adverse events. We now report 2-year outcomes. METHODS:We randomly assigned 301 patients to undergo either CABG alone or the combined procedure. Patients were followed for 2 years for clinical and echocardiographic outcomes. RESULTS:At 2 years, the mean (±SD) LVESVI was 41.2±20.0 ml per square meter of body-surface area in the CABG-alone group and 43.2±20.6 ml per square meter in the combined-procedure group (mean improvement over baseline, -14.1 ml per square meter and -14.6 ml per square meter, respectively). The rate of death was 10.6% in the CABG-alone group and 10.0% in the combined-procedure group (hazard ratio in the combined-procedure group, 0.90; 95% confidence interval, 0.45 to 1.83; P=0.78). There was no significant between-group difference in the rank-based assessment of the LVESVI (including death) at 2 years (z score, 0.38; P=0.71). The 2-year rate of moderate or severe residual mitral regurgitation was higher in the CABG-alone group than in the combined-procedure group (32.3% vs. 11.2%, P<0.001). Overall rates of hospital readmission and serious adverse events were similar in the two groups, but neurologic events and supraventricular arrhythmias remained more frequent in the combined-procedure group. CONCLUSIONS:In patients with moderate ischemic mitral regurgitation undergoing CABG, the addition of mitral-valve repair did not lead to significant differences in left ventricular reverse remodeling at 2 years. Mitral-valve repair provided a more durable correction of mitral regurgitation but did not significantly improve survival or reduce overall adverse events or readmissions and was associated with an early hazard of increased neurologic events and supraventricular arrhythmias. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00806988.).
PMID: 27040451
ISSN: 1533-4406
CID: 5451202
Management of severe asymmetric pectus excavatum complicating aortic repair in a patient with Marfan's syndrome [Case Report]
We describe the case of a 28-year old man with Marfan's syndrome and severe pectus excavatum who required an aortic root replacement for an ascending aortic aneurysm. There was a near-vertical angulation of the sternum that presented challenges with opening and exposure of the heart during aortic surgery. Furthermore, removal of the sternal retractor after aortic repair resulted in sudden loss of cardiac output. A Ravitch procedure was then performed to successfully close the chest without further cardiovascular compromise. We propose that patients with a severe pectus excavatum and mediastinal displacement seen on preoperative CT scanning should be considered for simultaneous, elective repair.
PMID: 26874148
ISSN: 1569-9285
CID: 5450032
Advances in aortic disease management: a year in review
PURPOSE OF REVIEW/OBJECTIVE:The medical and surgical management of aortic disease is continually changing in search for improved outcomes. Our objective is to highlight recent advances in a few select areas pertaining to aortic disease and aortic surgery: the genetics of aortopathy, medical therapy of aortic aneurysms, advances in cardiac imaging, and operative strategies for the aortic arch. RECENT FINDINGS/RESULTS:As our understanding of the genetic basis for aortopathy continues to improve, routine genetic testing may be of value in assessing patients with genetically triggered forms of aortic disease. With regard to medical advances, treating patients with Marfan syndrome with either losartan or atenolol at an earlier stage in their disease course improves outcomes. In addition, novel imaging indices such as wall shear stress and aortic stiffness assessed by MRI may become useful markers of aortopathy and warrant further study. With regard to the optimal technique for cerebral perfusion in aortic arch surgery, high-quality data are still lacking. Finally, in patients with complex, multilevel aortic disease, the frozen elephant trunk is a viable single-stage option compared with the conventional elephant trunk, although with an increased risk for spinal cord injury. SUMMARY/CONCLUSIONS:Based on recent advances, continued studies in genetics, cardiac imaging, and surgical trials will further elucidate the etiology of aortopathy and ultimately guide management, both medically and surgically.
PMID: 26766164
ISSN: 1531-7080
CID: 5450012
State-of-the-Art Surgical Management of Acute Type A Aortic Dissection
Acute type A aortic dissections still present a major challenge to cardiac surgeons. Although surgical management remains the gold standard, operative mortality remains high, including in experienced centres. Nevertheless, recent advances in the understanding and management of various aspects of these complex operations are expected to improve overall patient outcomes. The Canadian Thoracic Aortic Collaborative (CTAC) represents a group of surgeons with interest and expertise in the management of patients with aortic diseases. The purpose of this state-of-the-art review is to detail our approach to the contemporary surgical management of acute type A aortic dissections. We focus specifically on cannulation strategies, cerebral protection, and extent of proximal and distal resection. In addition, specific clinical scenarios-including malperfusion, intramural hematomas, and surgery in octogenarians-are explored.
PMID: 26604123
ISSN: 1916-7075
CID: 5450002
Innominate and Axillary Cannulation in Aortic Arch Surgery Provide Similar Neuroprotection
BACKGROUND:Contemporaneous trends in cerebral protection during aortic arch surgery include moderate hypothermia (22°C-28°C) and continuous antegrade cerebral perfusion (ACP). Innominate artery cannulation is a simplified, alternative route for ACP; however, clinical outcomes have yet to be evaluated against the gold standard of axillary cannulation. METHODS:Between 2008 and 2015, 140 consecutive patients underwent hemiarch reconstruction with moderate hypothermia and continuous ACP at 2 institutions. Axillary cannulation was used in 74 patients (31.1% female, 64.8 ± 12.7 years) and the remaining 66 patients (24.2% female, 60.8 ± 10.5 years) had direct cannulation of the innominate artery for delivery of ACP. RESULTS:Although there were no statistically significant differences in complications, neurological events were almost twice as frequent in innominate (19.7%) than in axillary (10.8%; P = 0.142) whereas prolonged mechanical ventilation was much more common with axillary (17.6%) vs innominate (7.6%; P = 0.078). There were no mortalities in the axillary group and 1 in the innominate group (0% vs 1.5%; P > 0.471) and no statistically significant differences in any other postoperative complications or hospital length of stay. There was a reduction in total operating room time in the innominate group (axillary 454 ± 115 minutes, innominate 318 ± 125 minutes; P < 0.001), and in the matched subgroup analysis of patients who underwent Bentall and hemiarch reconstruction (axillary 456 ± 109 minutes, innominate 370 ± 106 minutes; P = 0.003). CONCLUSIONS:Axillary and innominate artery cannulation for ACP during proximal aortic arch reconstructive surgery resulted in similarly excellent neurological outcomes. Innominate artery cannulation might reduce total surgical time. Possible clinically relevant differences in neurological and respiratory complications require assessment in randomized controlled trials.
PMID: 26549866
ISSN: 1916-7075
CID: 5451112
Journal of thoracic & cardiovascular surgery. 2015:150(4):824-31.e1.DOI: 10.1016/j.jtcvs.2015.07.026
Knowledge, attitudes, and practice preferences of Canadian cardiac surgeons toward the management of acute type A aortic dissection
OBJECTIVES/OBJECTIVE:The complexity of surgical treatment for acute type A dissection contributes to the variability in patient management. This study was designed to elucidate the contemporary practice preferences of cardiac surgeons regarding different phases of management of acute type A aortic dissection. METHODS:A 34-item questionnaire was distributed to all Canadian adult cardiac surgeons addressing the preoperative, intraoperative, and postoperative management of acute type A dissection. A total of 100 responses were obtained (82% of active surgeons in Canada). Outcomes were compared between high- and low-volume aortic surgeons. RESULTS:Seventy-six percent of respondents favored axillary artery cannulation. High-volume surgeons (>150 cases) were more likely to indicate a target lowest nasopharyngeal temperature more than 20 °C (53% vs 25%, P = .02). The majority of surgeons (65%) recommended using selective antegrade cerebral perfusion, with a significantly greater proportion for higher-volume aortic surgeons (P = .03). In addition, high-volume aortic surgeons were more likely to recommend aortic root replacement at smaller diameters (73% vs 55%, P = .02), to recommend more extensive distal aortic resection with routine open hemiarch anastomosis (85% vs 65%, P = .04), and to more commonly perform total arch reconstruction when needed (93% vs 77%, P = .04). In the follow-up period, frequency of serial imaging of the residual aorta was significantly higher for high-volume aortic surgeons (P = .04). CONCLUSIONS:This study identified some commonalities in practice preferences among Canadian cardiac surgeons for the management of acute type A aortic dissection. However, it also highlighted significant differences in temperature management, cerebral protection strategies, and extent of resection between high-volume and low-volume aortic surgeons.
PMID: 26277466
ISSN: 1097-685x
CID: 5449992
Balloon-Expandable and Self-Expanding Transcatheter Heart Valves: Friend or Foe? [Case Report]
Transcatheter aortic valve replacement (TAVR) with balloon-expandable (BE) or self-expanding (SE) transcatheter heart valves (THVs) is indicated for the treatment of high-risk patients with severe aortic stenosis. Limited data are available comparing the two THV designs, and evidence suggests that each may offer unique advantages. Herein are described two patients who underwent TAVR with BE-THV and SE-THV, and who each developed a device-related complication that was successfully treated by using the alternate THV design.
PMID: 26897845
ISSN: 0966-8519
CID: 5450042
Surgical treatment of moderate ischemic mitral regurgitation
BACKGROUND:Ischemic mitral regurgitation is associated with increased mortality and morbidity. For surgical patients with moderate regurgitation, the benefits of adding mitral-valve repair to coronary-artery bypass grafting (CABG) are uncertain. METHODS:We randomly assigned 301 patients with moderate ischemic mitral regurgitation to CABG alone or CABG plus mitral-valve repair (combined procedure). The primary end point was the left ventricular end-systolic volume index (LVESVI), a measure of left ventricular remodeling, at 1 year. This end point was assessed with the use of a Wilcoxon rank-sum test in which deaths were categorized as the lowest LVESVI rank. RESULTS:At 1 year, the mean LVESVI among surviving patients was 46.1±22.4 ml per square meter of body-surface area in the CABG-alone group and 49.6±31.5 ml per square meter in the combined-procedure group (mean change from baseline, -9.4 and -9.3 ml per square meter, respectively). The rate of death was 6.7% in the combined-procedure group and 7.3% in the CABG-alone group (hazard ratio with mitral-valve repair, 0.90; 95% confidence interval, 0.38 to 2.12; P=0.81). The rank-based assessment of LVESVI at 1 year (incorporating deaths) showed no significant between-group difference (z score, 0.50; P=0.61). The addition of mitral-valve repair was associated with a longer bypass time (P<0.001), a longer hospital stay after surgery (P=0.002), and more neurologic events (P=0.03). Moderate or severe mitral regurgitation was less common in the combined-procedure group than in the CABG-alone group (11.2% vs. 31.0%, P<0.001). There were no significant between-group differences in major adverse cardiac or cerebrovascular events, deaths, readmissions, functional status, or quality of life at 1 year. CONCLUSIONS:In patients with moderate ischemic mitral regurgitation, the addition of mitral-valve repair to CABG did not result in a higher degree of left ventricular reverse remodeling. Mitral-valve repair was associated with a reduced prevalence of moderate or severe mitral regurgitation but an increased number of untoward events. Thus, at 1 year, this trial did not show a clinically meaningful advantage of adding mitral-valve repair to CABG. Longer-term follow-up may determine whether the lower prevalence of mitral regurgitation translates into a net clinical benefit. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00806988.).
PMID: 25405390
ISSN: 1533-4406
CID: 5451212
Root replacement surgery versus more conservative management during type A acute aortic dissection repair
BACKGROUND:Aortic root management in type A acute aortic dissection is controversial. This study compared outcomes of root replacement (RR) interventions versus more conservative root (CR) management. METHODS:Of 1,995 type A acute aortic dissection patients enrolled in the International Registry of Acute Aortic Dissection, 699 (35%) underwent RR interventions and 1,296 (65%) underwent CR management. Independent predictors of hospital and 3-year survival were identified using multivariable logistic and Cox regression models. RESULTS:Compared with CR patients, RR patients were younger (56.9 versus 62.3 years; p = 0.023) and more likely to present with larger root diameter (4.7 cm versus 4.0 cm; p < 0.001), Marfan syndrome (8.7% versus 2.5%; p < 0.001), aortic insufficiency (64.0% versus 50.3%; p < 0.001), and hypotension, shock, or tamponade (33.0% versus 26.5%; p = 0.003). Root replacement management did not increase hospital mortality (propensity score-adjusted odds ratio, 1.14; p = 0.674). On Kaplan-Meier analysis, 3-year survival (RR, 92.5% ± 1.7% versus CR, 91.6% ± 1.3%; log-rank p = 0.623) and freedom from aortic root reintervention (RR, 99.2% ± 0.1% versus CR, 99.3% ± 0.1%; log-rank p = 0.770) were similar. Only 2 patients (1 per group) underwent follow-up root reintervention. Propensity score-adjusted Cox regression excluded a relationship between root treatment and follow-up survival (hazard ratio, 1.5; 95% confidence interval, 0.502 to 5.010; p = 0.432). CONCLUSIONS:In type A acute aortic dissection patients more-extensive RR interventions are not associated with increased hospital mortality. This supports such an approach in young patients and patients with connective tissue diseases and bicuspid aortic valves. Excellent midterm survival and freedom from root reintervention in both groups suggest stable behavior of the nonreplaced aortic sinuses at 3 years. Thus, pending studies with longer follow-up, the use of aggressive RR techniques can be determined by patient-specific and dissection-related factors.
PMID: 25282163
ISSN: 1552-6259
CID: 5449982
