Prashanth Vallabhajosyula

Hybrid approaches in the treatment of aortic arch aneurysms: Postoperative and midterm outcomes

BACKGROUND The combined open surgical and endovascular approach for the treatment of aortic arch aneurysms has emerged as a safe treatment modality. This platform may have an especially important role in treating patients of old age and with a greater comorbid burden. We describe our institutional experience with the hybrid aortic arch approach, with midterm outcomes. METHODS From 2005 to the present, 685 patients have undergone thoracic endovascular repair (TEVAR); 104 had a hybrid arch repair (open plus endovascular approach). Of these, 47 patients had treatment for an aortic arch aneurysm with or without a proximal ascending aortic aneurysm. All these patients had a median sternotomy approach for arch vessel debranching and antegrade with or without retrograde TEVAR stent grafting of the arch. Results from a prospectively maintained database are reported. RESULTS Twenty-eight patients had type I repair, 8 patients had type II repair, and 11 patients had type III arch hybrid repair. Those with type III repair were excluded from the analysis. Stent graft deployment rate was 100% after arch vessel debranching. Mean age was 71 ± 8 years. Fourteen percent of cases involved a redo sternotomy. Average cardiopulmonary bypass time was 215 ± 64 minutes, with a crossclamp time of 70 ± 55 minutes and a circulatory arrest time of 19 ± 10 minutes. The paraplegia rate was 5.5% (n = 2), with a stroke rate of 8% (n = 3). In-hospital mortality was 8% (n = 3). There were no postoperative endoleaks. The mean length of stay was 17.2 ± 14 days. The median follow-up was 30 ± 21 months. Freedom from all-cause mortality was 71%, 60%, and 48% at 1, 3, and 5 years, respectively. The aortic reoperation rate was 2.7% (n = 1). No patient has a type 1 or 3 endoleak at latest follow-up. CONCLUSIONS The hybrid approach to aortic arch aneurysm involving a zone 0 stent graft landing can be safely adopted with good midterm results in a cohort of old patients with significant comorbidity. This procedure can be performed with no type 1 or 3 endoleaks and may represent a technical advancement in the field of aortic arch surgery.

Extracorporeal life support as rescue strategy for out-of-hospital and emergency department cardiac arrest.

BACKGROUND Extracorporeal life support (ECLS) has been utilized as a rescue strategy for patients with cardiac arrest unresponsive to conventional cardiopulmonary resuscitation. OBJECTIVE We sought to describe our institutions experience with implementation of ECLS for out-of-hospital and emergency department (ED) cardiac arrests. Our primary outcome was survival to hospital discharge. METHODS Consecutive patients placed on ECLS in the ED or within one hour of admission after out-of-hospital or ED cardiac arrest were enrolled at two urban academic medical centers in the United States from July 2007-April 2014. RESULTS During the study period, 26 patients were included. Average age was 40±15 years, 54% were male, and 42% were white. Initial cardiac rhythms were ventricular fibrillation or pulseless ventricular tachycardia in 42%. The average time from initial cardiac arrest to initiation of ECLS was 77 ± 51 min (range 12-180 min). ECLS cannulation was unsuccessful in two patients. Eighteen (69%) had complications related to ECLS, most commonly bleeding and ischemic events. Four patients (15%) survived to discharge, three of whom were neurologically intact at 6 months. CONCLUSION ECLS shows promise as a rescue strategy for refractory out-of-hospital or ED cardiac arrest but is not without challenges. Further investigations are necessary to refine the technique, patient selection, and ancillary therapeutics.

In vivo imaging of autologous islet grafts in the liver and under the kidney capsule in non-human primates

Objective. As islet transplantation begins to show promise as a clinical method, there is a critical need for reliable, noninvasive techniques to monitor islet graft survival. Previous work in our laboratory has shown that human islets labeled with a superparamagnetic iron oxide contrast agent and transplanted into mice could be detected by magnetic resonance imaging (MRI). The potential translation of these findings to the clinical situation requires validation of our methodology in a non-human primate model, which we have now carried out in baboons (Papio hamadryas) and reported here. Research Design and Methods. For islet labeling, we adapted the Food and Drug Administration-approved superparamagnetic iron oxide contrast agent, Feridex, which is used clinically for liver imaging. After partial pancreatectomy, Feridex-labeled islets were prepared and autotransplanted underneath the renal capsule and into the liver. Longitudinal in vivo MRI at days 1, 3, 8, 16, 23, and 30 after transplantation was performed to track the islet grafts. Results. The renal subcapsular islet graft was easily detectable on T2*-weighted MR images as a pocket of signal loss disrupting the contour of the kidney at the transplantation site. Islets transplanted in the liver appeared as distinct signal voids dispersed throughout the liver parenchyma. A semiautomated computational analysis of our MRI data established the feasibility of monitoring both the renal and intrahepatic grafts during the studied posttransplantation period. Conclusion. This study establishes a method for the noninvasive, longitudinal detection of pancreatic islets transplanted into non-human primates using a low-field clinical MRI system.

Factors Associated With Vascular Complications in Patients Undergoing Balloon-Expandable Transfemoral Transcatheter Aortic Valve Replacement via Open Versus Percutaneous Approaches

Background—Vascular complications after transfemoral transcatheter aortic valve replacement are common and associated with significant morbidity and mortality. Little is known about the effect of access approach on vascular complications. Methods and Results—Between 2007 and 2013, 331 patients underwent transfemoral transcatheter aortic valve replacement via open surgical (OS) or fully percutaneous (PC) approaches. Patient data and clinical outcomes were collected. Valve Academic Research Consortium–defined vascular complications were noted. Multivariable analysis with propensity matching was performed, and vascular complications, mortality, and length of stay were assessed. One hundred twenty patients were treated with the OS approach and 211 patients via the PC approach. There were fewer major vascular complications (11% versus 20%; P=0.03) and shorter length of stay (7.5 versus 9.9 days; P=0.003) in the PC group when compared with those in the OS group. In multivariable analysis, vascular complications were more likely in women (odds ratio, 2.2; P=0.02) and with increasing differences between sheath outer diameter and minimal artery diameter (overall vascular complications: odds ratio, 1.4; P=0.02 and major vascular complications: odds ratio, 2.0; P<0.001). Propensity-matched analysis demonstrated no difference in vascular complications between the OS and the PC groups (22% versus 19%; P=0.73) but significantly reduced length of stay in the PC group (7.9 versus 10.0 days; P=0.04). Conclusions—Transfemoral transcatheter aortic valve replacement performed via the PC route is associated with similar risk of vascular complications and significantly lower postprocedural length of stay than the OS route. The degree of sheath oversizing with respect to iliofemoral minimal artery diameter and female sex are associated with vascular complications regardless of access approach.

Long-term results of aggressive hemiarch replacement in 534 patients with type A aortic dissection

OBJECTIVE To present the outcomes of routinely performed hemiarch replacement in patients with acute type A aortic dissection. METHODS From 1993 to 2013, among 629 patients with acute type A dissection, 534 patients (85%) underwent hemiarch, 63 patients (10%) underwent hemiarch and antegrade thoracic stent grafting, 26 patients (4%) underwent total arch, and 6 patients (1%) underwent isolated ascending replacement. Patients with hemiarch replacement comprised the study population. Median follow-up was 4.1 years (first quartile, 1.9; third quartile, 7.8) (2462 patient years). RESULTS In-hospital mortality was 12% (66 out of 534 patients). Survival was 80% ± 2%, 68% ± 3%, and 51% ± 3%, and 84% ± 3%, 65% ± 4%, and 41% ± 6% in DeBakey type I and II patients at 1, 5, and 10 years, respectively (log rank P = .375). Freedom from distal aortic reintervention was 97% ± 1%, 90% ± 2%, and 85% ± 3% and 99% ± 1%, 97% ± 2%, and 90% ± 5% in DeBakey type I and II patients at 1, 5, and 10 years, respectively (log rank P = .046). Seven patients (1.3%) required reintervention for aortic arch aneurysm and 25 patients (5%) required reintervention for descending aortopathy. The success rate for distal reintervention performed electively or urgently was 92% (24 out of 26 patients). Marfan syndrome (odds ratio, 3.43; P = .046) and DeBakey type I dissection (odds ratio, 2.49; P = .048) were independent predictors of distal aortic reintervention. CONCLUSIONS Aggressive hemiarch replacement in acute type A dissection can be performed with low mortality and low aortic arch reoperation rate. Resection of all dissected aortic wall tissue decreases, but does not eliminate, the risk of later adverse aortic events.

Modeling of predissection aortic size in acute type A dissection: More than 90% fail to meet the guidelines for elective ascending replacement.

OBJECTIVES The current guidelines for ascending aortic replacement were determined from already dissected aorta diameters. Previous computed tomography-based work on humans who underwent imaging before and directly after aortic dissection onset has shown an average 30% increase in the ascending aortic diameter with acute dissection. The present investigation evaluated the incidence of predissection ascending aortic dilatation in acute type A dissection. METHODS From 2002 to 2013, 495 patients presented with acute type A aortic dissection to 1 center. Of these cases, 343 were non-Marfan, nonbicuspid with spontaneous dissection etiology. In those with available preoperative computed tomography angiograms (n = 83) or transesophageal echocardiograms (n = 260), the predissection ascending aorta diameters were modeled from the dissected aorta diameters by subtraction of the average diameter increase rate. RESULTS Altogether 343 patients were included (age, 62 years; range, 53-73; 64% men). The median modeled predissection ascending diameter was 3.7 cm (first quartile, 3.3; third quartile, -4.1). Of the 343 patients, 334 (97%) and 315 (92%) had an ascending diameter before dissection onset of <5.5 cm and <5.0 cm, respectively. More than 60% of women and 70% of men had a nondilated ascending aorta before type A dissection onset. The median predissection ascending aortic diameter did not differ between women and men (3.7 cm; first quartile, 3.4; third quartile, 4.2; vs 3.7 cm; first quartile, 3.3; third quartile, 4.1; P = .810). CONCLUSIONS More than 60% of patients with spontaneous, non-Marfan, nonbicuspid, type A dissection will have a nondilated ascending aorta before dissection onset. Only 3% would meet the criteria for elective ascending replacement to prevent aortic dissection. Additional research on the genetic and biochemical predictors of aortic dissection is essential.

Type A Aortic Dissection in Marfan Syndrome Extent of Initial Surgery Determines Long-Term Outcome

Background— Data on outcomes after Stanford type A aortic dissection in patients with Marfan syndrome are limited. We investigated the primary surgery and long-term results in patients with Marfan syndrome who suffered aortic dissection. Methods and Results— Among 1324 consecutive patients with aortic dissection type A, 74 with Marfan syndrome (58% men; median age, 37 years [first and third quartiles, 29 and 48 years]) underwent surgical repair (85% acute dissections; 68% DeBakey I; 55% composite valved graft, 30% supracoronary ascending replacement, 15% valve-sparing aortic root replacement; 12% total arch replacement; 3% in-hospital mortality) at 2 tertiary centers in the United States and Europe over the past 25 years. The rate of aortic reintervention with resternotomy was 24% (18 of 74) and of descending aorta (thoracic+abdominal) intervention was 30% (22 of 74) at a median follow-up of 8.4 years (first and third quartiles, 2.2 and 12.7 years). Freedom from need for aortic root reoperation in patients who underwent primarily a composite valved graft or valve-sparing aortic root replacement procedure was 95±3%, 88±5%, and 79±5% and in patients who underwent supracoronary ascending replacement was 83±9%, 60±13%, 20±16% at 5, 10, and 20 years. Secondary aortic arch surgery was necessary only in patients with initial hemi-arch replacement. Conclusions— Emergency surgery for type A dissection in patients with Marfan syndrome is associated with low in-hospital mortality. Failure to extend the primary surgery to aortic root or arch repair leads to a highly complex clinical course. Aortic root replacement or repair is highly recommended because supracoronary ascending replacement is associated with a high need (>40%) for root reintervention. # CLINICAL PERSPECTIVE {#article-title-23}Background— Data on outcomes after Stanford type A aortic dissection in patients with Marfan syndrome are limited. We investigated the primary surgery and long-term results in patients with Marfan syndrome who suffered aortic dissection. Methods and Results— Among 1324 consecutive patients with aortic dissection type A, 74 with Marfan syndrome (58% men; median age, 37 years [first and third quartiles, 29 and 48 years]) underwent surgical repair (85% acute dissections; 68% DeBakey I; 55% composite valved graft, 30% supracoronary ascending replacement, 15% valve-sparing aortic root replacement; 12% total arch replacement; 3% in-hospital mortality) at 2 tertiary centers in the United States and Europe over the past 25 years. The rate of aortic reintervention with resternotomy was 24% (18 of 74) and of descending aorta (thoracic+abdominal) intervention was 30% (22 of 74) at a median follow-up of 8.4 years (first and third quartiles, 2.2 and 12.7 years). Freedom from need for aortic root reoperation in patients who underwent primarily a composite valved graft or valve-sparing aortic root replacement procedure was 95±3%, 88±5%, and 79±5% and in patients who underwent supracoronary ascending replacement was 83±9%, 60±13%, 20±16% at 5, 10, and 20 years. Secondary aortic arch surgery was necessary only in patients with initial hemi-arch replacement. Conclusions— Emergency surgery for type A dissection in patients with Marfan syndrome is associated with low in-hospital mortality. Failure to extend the primary surgery to aortic root or arch repair leads to a highly complex clinical course. Aortic root replacement or repair is highly recommended because supracoronary ascending replacement is associated with a high need (>40%) for root reintervention.

Conscious Sedation Versus General Anesthesia for Transcatheter Aortic Valve Replacement: Insights from the National Cardiovascular Data Registry Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry

Background: Conscious sedation is used during transcatheter aortic valve replacement (TAVR) with limited evidence as to the safety and efficacy of this practice. Methods: The National Cardiovascular Data Registry Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry was used to characterize the anesthesia choice and clinical outcomes of all US patients undergoing elective percutaneous transfemoral TAVR between April 1, 2014, and June 30, 2015. Raw and inverse probability of treatment-weighted analyses were performed to compare patients undergoing TAVR with general anesthesia with patients undergoing TAVR with conscious sedation on an intention-to-treat basis for the primary outcome of in-hospital mortality, and secondary outcomes including 30-day mortality, in-hospital and 30-day death/stroke, procedural success, intensive care unit and hospital length-of-stay, and rates of discharge to home. Post hoc falsification end point analyses were performed to evaluate for residual confounding. Results: Conscious sedation was used in 1737/10 997 (15.8%) cases with a significant trend of increasing usage over the time period studied (P for trend<0.001). In raw analyses, intraprocedural success with conscious sedation and general anesthesia was similar (98.2% versus 98.5%, P=0.31). The conscious sedation group was less likely to experience in-hospital (1.6% versus 2.5%, P=0.03) and 30-day death (2.9% versus 4.1%, P=0.03). Conversion from conscious sedation to general anesthesia was noted in 102 of 1737 (5.9%) of conscious sedation cases. After inverse probability of treatment-weighted adjustment for 51 covariates, conscious sedation was associated with lower procedural success (97.9% versus 98.6%, P<0.001) and a reduced rate of mortality at the in-hospital (1.5% versus 2.4%, P<0.001) and 30-day (2.3% versus 4.0%, P<0.001) time points. Conscious sedation was associated with reductions in procedural inotrope requirement, intensive care unit and hospital length of stay (6.0 versus 6.5 days, P<0.001), and combined 30-day death/stroke rates (4.8% versus 6.4%, P<0.001). Falsification end point analyses of vascular complications, bleeding, and new pacemaker/defibrillator implantation demonstrated no significant differences between groups after adjustment. Conclusions: In US practice, conscious sedation is associated with briefer length of stay and lower in-hospital and 30-day mortality in comparison with TAVR with general anesthesia in both unadjusted and adjusted analyses. These results suggest the safety of conscious sedation in this population, although comparative effectiveness analyses using observational data cannot definitively establish the superiority of one technique over another.Background —Conscious sedation is used during transcatheter aortic valve replacement (TAVR) with limited evidence as to the safety and efficacy of this practice. Methods —The NCDR STS/ACC TVT Registry was used to characterize the anesthesia choice and clinical outcomes of all U.S. patients undergoing elective percutaneous transfemoral TAVR between April 1, 2014 and June 30, 2015. Raw and inverse probability of treatment weighted (IPTW) analyses were performed to compare general anesthesia patients with conscious sedation patients on an intention-to-treat basis for the primary outcome of in-hospital mortality, and secondary outcomes including 30-day mortality, in-hospital and 30-day death/stroke, procedural success, ICU and hospital length-of-stay, and rates of discharge to home. Post-hoc falsification endpoint analyses were performed to evaluate for residual confounding. Results —Conscious sedation was used in 1,737/10,997 (15.8%) cases with a significant trend of increasing usage over the time period studied (p for trend Conclusions —In U.S. practice, conscious sedation is associated with briefer length of stay and lower in-hospital and 30-day mortality compared to TAVR with general anesthesia in both unadjusted and adjusted analyses. These results suggest the safety of conscious sedation in this population, though comparative effectiveness analyses using observational data cannot definitively establish the superiority of one technique over another.

Root Stabilization of the Repaired Bicuspid Aortic Valve: Subcommissural Annuloplasty Versus Root Reimplantation

BACKGROUND At our institution, type I bicuspid aortic valve (BAV) patients with aortic insufficiency (AI) who are candidates for valve preservation are stratified into two groups by aortic root pathology: nonaneurysmal root undergoing primary cusp repair+subcommissural annuloplasty (repair group) vs aneurysmal root undergoing primary cusp repair+root reimplantation (reimplantation group). We report outcomes of this surgical reconstructive strategy for the repaired type I BAV. METHODS A retrospective review was performed of 71 patients with a type I BAV undergoing primary valve repair from 2005 to 2012. The repair group (n=40) underwent annular stabilization by subcommissural annuloplasty, and the reimplantation group (n=31) underwent robust annular stabilization provided by root reimplantation. RESULTS Preoperative characteristics and root anatomy were similar, except for increased root dimensions in the reimplantation group (p<0.001). Mortality, stroke, valve reoperation, and pacemaker requirement were zero in both groups. Postoperative peak (19±10 vs 11±5 mm Hg, p<0.001) and mean gradients (10±5 vs 5±3 mm Hg, p<0.001) favored root reimplantation. Freedom from AI greater than 1+ was 100% in both groups. Mean follow-up was 40 months in the reimplantation group and 38 months in the repair group. At 5 years, overall survival was 100% in both groups. Freedom from aortic reoperation and AI exceeding 2+ were similar in both groups. Freedom from AI exceeding 1+ was significantly better in the reimplantation group (92%±6% vs 62%±10%, p=0.03). The 2-year peak (14±6 vs 19±9 mm Hg, p=0.009) and mean (7±4 vs 11±5 mm Hg, p=0.001) gradients favored root reimplantation. CONCLUSIONS Root stabilization with the reimplantation technique significantly improves the durability of the repaired type I BAV compared with subcommissural annuloplasty. It also provides improved and sustained valve mobility (transvalvular gradients).

Long-Term Results of Neomedia Sinus Valsalva Repair in 489 Patients With Type A Aortic Dissection

BACKGROUND Acute type A aortic dissection frequently occurs in patients with normally sized aortic roots. The aim of this investigation was to describe the durability of aortic valve resuspension and root repair with a novel technique of reconstruction in type A dissection. METHODS From 1993 to 2013, among 629 patients operated on for acute type A dissection 489 (62% male, median age 62 years (53; 73) underwent aortic valve resuspension and reinforcement of the sinus of Valsalva with a Teflon felt neomedia. The median follow-up time was 4.1 years (1.3; 6.8) (2075 patient-years). RESULTS In-hospital mortality was 11% (56/489). Survival was 69%±2%, 50%±3%, and 36%±5% at 5, 10, and 15 years, respectively. Freedom from moderate or severe aortic regurgitation was not influenced by the aortic regurgitation grade at the initial operation (p=0.131). Freedom from proximal aortic reoperation was 96%±1%, 92%±2%, and 89%±4% at 5, 10, and 15 years, respectively. Seventeen patients (3%) required proximal reoperation: 10 for aortic regurgitation, including 3 with concomitant pseudoaneurysm and 2 with root aneurysm; 6 for pseudoaneurysm; and 1 for graft infection. CONCLUSIONS Aortic root neomedia reconstruction and valve resuspension can be successfully performed in the majority of patients with type A dissection. The in-hospital mortality is low, and the results are durable.