Faculty Bibliography
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145
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
Efficacy and safety of early parenteral anticoagulation as a bridge to warfarin after mechanical valve replacement
Limited evidence exists to guide the use of early parenteral anticoagulation following mechanical heart valve replacement (MVR). The purpose of this study was to compare the 30-day rates of thrombotic and bleeding complications for MVR patients receiving therapeutic versus prophylactic dose bridging regimens. In this retrospective cohort study we reviewed anticoagulation management and outcomes of all patients undergoing MVR at five Canadian hospitals between 2003 and 2010. The primary efficacy outcome was thromboembolism (stroke, transient ischaemic attack, systemic embolism or valve thrombosis) and the primary safety outcome was major bleeding at 30-days. Outcomes were compared using a logistic regression model adjusting for propensity score and in a 1:1 propensity matched sample. A total of 1777 patients underwent mechanical valve replacement, of whom 923 received therapeutic dose bridging anticoagulation and 764 received prophylactic dose bridging postoperatively. Sixteen patients (1.8 %) who received therapeutic dose bridging and fifteen patients (2.1 %) who received prophylactic dose bridging experienced the primary efficacy outcome (odds ratio [OR] 0.90; 95 % confidence interval [CI], 0.37 to 2.18, p=0.81). Forty-eight patients (5.4 %) in the therapeutic dosing group and 14 patients (1.9 %) in the prophylactic dosing group experienced the primary safety outcome of major bleeding (OR 3.23; 95 % CI, 1.58 to 6.62; p=0.001). The direction of the effects, their magnitude and significance were maintained in the propensity matched analysis. In conclusion, we found that early after mechanical valve replacement, therapeutic dose bridging was associated with a similar risk of thromboembolic complications, but a 2.5 to 3-fold increased risk of major bleeding compared with prophylactic dose bridging.
PMID: 25183209
ISSN: 2567-689x
CID: 5449962
Direct innominate artery cannulation for selective antegrade cerebral perfusion during deep hypothermic circulatory arrest in aortic surgery
OBJECTIVE:To demonstrate a novel, reproducible, and effective method of direct innominate artery cannulation using a 14 F pediatric venous cannula to establish antegrade cerebral protection (ACP) in patients undergoing aortic surgery that requires an open distal anastomosis or hemiarch replacement. METHODS:We reviewed prospectively gathered data on all patients who had undergone replacement of the ascending aorta or hemiarch with an open distal anastomosis using deep hypothermic circulatory arrest and direct innominate artery cannulation with a 14 F pediatric venous cannula at our institution. After central cannulation and cooling to 25 °C to 28 °C, all patients had ACP initiated by way of a direct innominate cannula placed over a guidewire. RESULTS:Fifty patients underwent direct innominate artery cannulation with our technique from 2010 to 2012. The operative mortality was 2% (n = 1), and the rates of neurologic morbidity were acceptable and similar to those with other methods of ACP delivery: stroke (2%, n = 1), seizure (0%, n = 0), and delirium (18%, n = 9). The mean operative time was 31 ± 9, 19 ± 5, 100 ± 39, 141 ± 39, and 259 ± 63 minutes for cooling, circulatory arrest, crossclamp, cardiopulmonary bypass, and total operative time, respectively. No local or arterial complications were observed. CONCLUSIONS:Direct cannulation of the innominate artery using a 14 F pediatric venous cannula is a simple, reproducible, safe, and effective technique for establishing ACP in patients undergoing aortic surgery that requires an open distal anastomosis or hemiarch replacement. This technique avoids the additional time and potential local complications associated with other established methods for delivering ACP, such as axillary cannulation.
PMID: 25172323
ISSN: 1097-685x
CID: 5449952
Impact of wait times on the effectiveness of transcatheter aortic valve replacement in severe aortic valve disease: a discrete event simulation model
BACKGROUND:There is increasing demand for transcatheter aortic valve replacement (TAVR) as the primary treatment option for patients with severe aortic stenosis who are high-risk surgical candidates or inoperable. We used mathematical simulation models to estimate the hypothetical effectiveness of TAVR with increasing wait times. METHODS:We applied discrete event modelling, using data from the Placement of Aortic Transcatheter Valves (PARTNER) trials. We compared TAVR with medical therapy in the inoperable cohort, and compared TAVR to conventional aortic valve surgery in the high-risk cohort. One-year mortality and wait-time deaths were calculated in different scenarios by varying TAVR wait times from 10 days to 180 days, while maintaining a constant wait time for surgery at a mean of 15.6 days. RESULTS:In the inoperable cohort, the 1-year mortality for medical therapy was 50%. When the TAVR wait time was 10 days, the TAVR wait-time mortality was 1.9% with a 1-year mortality of 31.5%. TAVR wait-time deaths increased to 28.9% with a 180-day wait, with a 1-year mortality of 41.4%. In the high-risk cohort, the wait-time deaths and 1-year mortality for the surgical patients were 2.5% and 27%, respectively. The TAVR wait-time deaths increased from 2.2% with a 10-day wait to 22.4% with a 180-day wait, and a corresponding increase in 1-year mortality from 24.5% to 32.6%. Mortality with TAVR exceeded surgery when TAVR wait times exceeded 60 days. CONCLUSIONS:Modest increases in TAVR wait times have a substantial effect on the effectiveness of TAVR in inoperable patients and high-risk surgical candidates.
PMID: 25047363
ISSN: 1916-7075
CID: 5451102
Transcatheter mitral valve implantation (TMVI) using the Edwards FORTIS device
Transcatheter aortic valve implantation (TAVI) has demonstrated the feasibility of treating valvular heart disease with transcatheter therapy. On the back of this success, various transcatheter concepts are being evaluated to treat other valvular disease, especially mitral regurgitation (MR). The concepts currently approved to treat MR replicate surgical mitral valve repair. However, most of them cannot eliminate MR completely. Similar to TAVI, a transcatheter mitral valve implantation may provide a valuable alternative. The FORTIS transcatheter mitral valve (Edwards Lifesciences, Irvine, CA, USA) is a self-expanding device implanted via a transapical approach. We describe our experience and early results in the first five patients treated on compassionate grounds. We also describe the details of the device, selection criteria and technical details of implantation.
PMID: 25256325
ISSN: 1969-6213
CID: 5449972
Acute Type A Dissection Repair in an Achondroplastic Dwarf: Anesthetic, Perfusion, and Surgical Concerns [Case Report]
In this report we present a 43-year-old male with achondroplastic dwarfism who presented with acute Type A aortic dissection with aortic insufficiency. The patient underwent successful Bentall and hemiarch repair. Anesthetic, perfusion-related, and surgical planning and execution are presented.
PMCID:4682726
PMID: 26798732
ISSN: 2325-4637
CID: 5450022
Pulse pressure and type A acute aortic dissection in-hospital outcomes (from the International Registry of Acute Aortic Dissection)
Little is known about the relation between type A acute aortic dissection (TAAAD) and pulse pressure (PP), defined as the difference between systolic and diastolic blood pressure. In this study, we explored the association between PP and presentation, complications, and outcomes of patients with TAAAD. PP at hospital presentation was used to divide 1,960 patients with noniatrogenic TAAAD into quartiles: narrowed (≤39 mm Hg, n=430), normal (40 to 56 mm Hg, n=554), mildly elevated (57 to 75 mm Hg, n=490), and markedly elevated (≥76 mm Hg, n=486). Variables relating to index presentation and in-hospital outcomes were analyzed. Patients with TAAAD in the narrowed PP quartiles were frequently older and Caucasian, whereas patients with markedly elevated PPs tended to be male and have a history of hypertension. Patients who demonstrated abdominal vessel involvement more commonly demonstrated elevated PPs, whereas patients with narrowed PPs were more likely to have periaortic hematoma and/or pericardial effusion. Narrowed PPs were also correlated with greater incidences of hypotension, cardiac tamponade, and mortality. Patients with TAAAD who were managed with endovascular and hybrid procedures and those with renal failure tended to have markedly elevated PPs. No difference in aortic regurgitation at presentation was noted among groups. In conclusion, patients with TAAAD in the third PP quartile had better in-hospital outcomes than patients in the lowest quartile. Patients with narrowed PPs experienced more cardiac complications, particularly cardiac tamponade, whereas those with markedly elevated PPs were more likely to have abdominal aortic involvement. Presenting PP offers a clue to different manifestations of acute aortic dissection that may facilitate initial triage and care.
PMID: 24521716
ISSN: 1879-1913
CID: 5449932
Impact of new-onset persistent left bundle branch block on late clinical outcomes in patients undergoing transcatheter aortic valve implantation with a balloon-expandable valve
OBJECTIVES/OBJECTIVE:The aim of this study was to determine the impact of new-onset persistent left bundle branch block (NOP-LBBB) on late outcomes after transcatheter aortic valve implantation (TAVI). BACKGROUND:The impact of NOP-LBBB after TAVI remains controversial. METHODS:A total of 668 consecutive patients who underwent TAVI with a balloon-expandable valve without pre-existing LBBB or permanent pacemaker implantation (PPI) were included. Electrocardiograms were obtained at baseline, immediately after the procedure, and daily until hospital discharge. Patients were followed at 1, 6, and 12 months and yearly thereafter. RESULTS:New-onset LBBB occurred in 128 patients (19.2%) immediately after TAVI and persisted at hospital discharge in 79 patients (11.8%). At a median follow-up of 13 months (range 3 to 27 months), there were no differences in mortality rate between the NOP-LBBB and no NOP-LBBB groups (27.8% vs. 28.4%; adjusted-hazard ratio: 0.87 [95% confidence interval (CI): 0.55 to 1.37]; p = 0.54). There were no differences between groups regarding cardiovascular mortality (p = 0.82), sudden death (p = 0.87), rehospitalizations for all causes (p = 0.11), or heart failure (p = 0.55). NOP-LBBB was the only factor associated with an increased rate of PPI during the follow-up period (13.9% vs. 3.0%; hazard ratio: 4.29 [95% CI: 2.03 to 9.07], p < 0.001. NOP-LBBB was also associated with a lack of left ventricular ejection fraction improvement and poorer New York Heart Association functional class at follow-up (p < 0.02 for both). CONCLUSIONS:NOP-LBBB occurred in ∼1 of 10 patients who had undergone TAVI with a balloon-expandable valve. NOP-LBBB was associated with a higher rate of PPI, a lack of improvement in left ventricular ejection fraction, and a poorer functional status, but did not increase the risk of global or cardiovascular mortality or rehospitalizations at 1-year follow-up.
PMID: 24440024
ISSN: 1876-7605
CID: 5451092
The role of age in complicated acute type B aortic dissection
BACKGROUND: Complicated acute type B aortic dissection (cABAD) generally requires urgent intervention. Advanced age is a risk factor for mortality after thoracic aortic intervention, including surgery for aortic dissection. The purpose of this study was to investigate the exact impact of increasing age on the management and outcomes of cABAD. METHODS: We analyzed the outcomes of 583 patients with cABAD enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2012. All patients with cABAD were categorized according to age by decade and management type (medical, surgical, or endovascular treatment), and outcomes were subsequently investigated in the different age groups. RESULTS: The mean age of the cohort was 63.4 +/- 14.2 years, 36% of patients (n = 209) were greater than 70 years of age and 64% (n = 374) were less than 70 years. The utilization of surgery and endovascular techniques progressively decreased with patient age, while the rate of medical management significantly increased with age (p < 0.001). The in-hospital mortality rates for complicated patients younger than 70 years versus 70 years or more were 10.1% versus 30.0% for endovascular treatment (p = 0.001), 17.2% versus 34.2% for surgical treatment (p = 0.027), and 14.2% versus 32.2% for medical treatment (p = 0.001). Age 70 years or greater was a predictor of in-hospital mortality in multivariate analysis (odds ratio 2.37, 95% confidence interval: 1.23 to 4.54, p = 0.010). CONCLUSIONS: Advanced age has a dramatic impact on the management and outcomes of patients with cABAD. A nonsignificant trend toward lower mortality after endovascular management was observed, both for younger patients and for elderly patients.
PMID: 24070705
ISSN: 0003-4975
CID: 927692
