Successful Treatment of Severe Paravalvular Leak by Repositioning a Self-Expandable Percutaneous Aortic Valve Bioprosthesis (Evolut PRO+) Using the "Double Snare" Technique.

Significant (moderate or severe) paravalvular leak (PVL) after transcatheter aortic valve replacement (TAVR) remains a common phenomenon and has been associated with decrease survival and quality of life. Transcatheter valve embolization and migration (TVEM) is a rare post-TAVR complication that can occur in 1% of cases and has been associated with worse patient outcomes. Valve embolization or migration into the left ventricle can result in significant PVL causing hemodynamic instability, shock, heart failure, and hemolytic anemia. Although this complication most commonly occurs in the acute setting (90%) within 4 hours of TAVR, it can also present late (4 hr-43 days later) in 10% of cases. There are no clear guidelines as to how this condition should be managed; however, several percutaneous bailout techniques exist that can ultimately spare the patient from emergent cardiovascular surgery. We present a rare case of late ventricular transcatheter aortic valve migration 3 days after TAVR causing severe PVL and heart failure symptoms that was successfully treated using the percutaneous "double snare" technique.

Experience with Percutaneous Transcatheter Closure of Interatrial Communications at the Cardiovascular Center of Puerto Rico and the Caribbean.

OBJECTIVE: The annual rate of percutaneous transcatheter closure of atrial septal defects (ASDs) and patent foramen ovales (PFO) has markedly increased in the United States over the past decade. This technique has been used at the Cardiovascular Center for Puerto Rico and the Caribbean since 2005. We report on the clinical characteristics and the immediate and short-term follow-up of adult patients who underwent this procedure at this center from 2008 to 2012. METHODS: One hundred and two consecutive medical records of adult Hispanic patients who underwent this procedure at our center from 2008 to 2012 were identified. A retrospective analysis of the clinical characteristics and the immediate and short-term clinical and echocardiographic follow-up of those patients was performed. RESULTS: The study population comprised 70 women and 32 men, with a mean age of 51 years (age range: 19 to 80 years). Of those, 43 (42%) underwent ASD closure and 60 (59%), closure of a PFO. A 99% procedural success rate was achieved. There were only 3 procedural complications, including the failure of the initial implantation of 1 device, which required the endovascular removal of that device and the implantation of another, a hematoma at the vascular access site, and 1 brief episode of atrial fibrillation. CONCLUSION: Based on our review of the available records, we were able to determine that the percutaneous transcatheter closure of interatrial communications proved to be, at our institution, a safe procedure with a high success rate and a low incidence of in-hospital complications. To our knowledge, this is the first report on the utilization of this interventional procedure in Puerto Rico.

Randomized controlled study of excimer laser atherectomy for treatment of femoropopliteal in-stent restenosis: initial results from the EXCITE ISR trial (EXCImer Laser Randomized Controlled Study for Treatment of FemoropopliTEal In-Stent Restenosis).

OBJECTIVES: The purpose of this study was to evaluate the safety and efficacy of excimer laser atherectomy (ELA) with adjunctive percutaneous transluminal angioplasty (PTA) versus PTA alone for treating patients with chronic peripheral artery disease with femoropopliteal bare nitinol in-stent restenosis (ISR). BACKGROUND: Femoropopliteal stenting has shown superiority to PTA for lifestyle-limiting claudication and critical limb ischemia, although treating post-stenting artery reobstruction, or ISR, remains challenging. METHODS: The multicenter, prospective, randomized, controlled EXCITE ISR (EXCImer Laser Randomized Controlled Study for Treatment of FemoropopliTEal In-Stent Restenosis) trial was conducted across 40 U.S. centers. Patients with Rutherford Class 1 to 4 and lesions of target lesion length ≥4 cm, vessel diameter 5 to 7 mm were enrolled and randomly divided into ELA + PTA and PTA groups by a 2:1 ratio. The primary efficacy endpoint was target lesion revascularization (TLR) at 6-month follow up. The primary safety endpoint was major adverse event (death, amputation, or TLR) at 30 days post-procedure. RESULTS: Study enrollment was stopped at 250 patients due to early efficacy demonstrated at a prospectively-specified interim analysis. A total of 169 ELA + PTA subjects (62.7% male; mean age 68.5 ± 9.8 years) and 81 PTA patients (61.7% male; mean age 67.8 ± 10.3 years) were enrolled. Mean lesion length was 19.6 ± 12.0 cm versus 19.3 ± 11.9 cm, and 30.5% versus 36.8% of patients exhibited total occlusion. ELA + PTA subjects demonstrated superior procedural success (93.5% vs. 82.7%; p = 0.01) with significantly fewer procedural complications. ELA + PTA and PTA subject 6-month freedom from TLR was 73.5% versus 51.8% (p < 0.005), and 30-day major adverse event rates were 5.8% versus 20.5% (p < 0.001), respectively. ELA + PTA was associated with a 52% reduction in TLR (hazard ratio: 0.48; 95% confidence interval: 0.31 to 0.74). CONCLUSIONS: The EXCITE ISR trial is the first large, prospective, randomized study to demonstrate superiority of ELA + PTA versus PTA alone for treating femoropopliteal ISR. (Randomized Study of Laser and Balloon Angioplasty Versus Balloon Angioplasty to Treat Peripheral In-stent Restenosis [EXCITE ISR]; NCT01330628).

Sildenafil improves coronary artery patency in a canine model of platelet-mediated cyclic coronary occlusion after thrombolysis.

OBJECTIVES: We sought to assess the effect of sildenafil, a highly-specific type 5 phosphodiesterase (PDE5) inhibitor, on platelet-mediated cyclic coronary flow reductions occurring in a canine model of coronary thrombosis despite aspirin therapy. BACKGROUND: The PDE5 inhibitors augment the antithrombotic effects of nitric oxide in vitro and in vivo, but it has been proposed that the PDE5 inhibitor sildenafil is prothrombotic. METHODS: Cyclic coronary flow reductions were induced in the left anterior descending coronary artery by creation of a stenosis, endothelial injury, and thrombus formation followed by treatment with aspirin, heparin, and tissue plasminogen activator. After an initial observation period, dogs were treated with or without sildenafil (100 microg/kg bolus followed by 4 microg/kg/min infusion). RESULTS: Cyclic coronary flow reductions ceased in five of six animals 18 +/- 5 min after initiation of sildenafil but continued in all six control animals. The portion of the observation period during which the coronary artery was patent increased from 52 +/- 9% to 83 +/- 5% after sildenafil administration (p = 0.008) but did not differ between the first and second observation periods in untreated dogs (49 +/- 11% vs. 44 +/- 11%, respectively). Among animals with plasma free sildenafil levels > or =20 nmol/l, cyclic coronary flow reductions were 73 +/- 12% less frequent and the time to cessation of cycling 72 +/- 14% shorter than in animals with levels <20 nmol/l (p < 0.05 for both). Sildenafil transiently decreased blood pressure 7 +/- 1% but did not change heart rate. Sildenafil treatment reduced ex vivo thrombin-induced platelet aggregation by 39 +/- 3% (p < 0.005). CONCLUSIONS: Sildenafil improves coronary patency in a canine model of platelet-mediated coronary artery thrombosis, likely via inhibition of platelet aggregation.

Transthoracic left ventricular puncture for the assessment of patients with aortic and mitral valve prostheses: the Massachusetts General Hospital experience, 1989-2000.

Accurate assessment of suspected prosthetic valve dysfunction is critically important as reoperation carries high risk. Noninvasive methods of hemodynamic assessment of patients with both aortic and mitral mechanical valves continue to be frustrated by the interference created by prosthetic material and direct left ventricular puncture may be required for definitive hemodynamic assessment. We report the hemodynamic and angiographic results and outcomes of 38 consecutive patients with double valve replacement who underwent left ventricular puncture as part of evaluation of possible prosthetic dysfunction. These results were compared with those obtained by noninvasive testing. We found noninvasive assessment alone to be unsatisfactory as measurements of regurgitation and stenosis correlated poorly with those obtained by direct left ventricular puncture. Important information that altered patient management was obtained from invasive assessment in 68% of cases with an acceptable rate of complications. Therefore, hemodynamic and angiographic assessment using transthoracic left ventricular puncture should be entertained in patients with mitral and aortic valve replacement presenting with congestive heart failure and suspected prosthesis dysfunction.

Directional coronary atherectomy vs. rotational atherectomy for the treatment of in-stent restenosis of native coronary arteries.

Management of in-stent restenosis has become a significant challenge in interventional cardiology. Since the mechanism of in-stent restenosis is predominantly intimal hyperplasia, debulking techniques have been used to treat this condition. This study is a nonrandomized comparison of the immediate and long-term results of directional coronary atherectomy (DCA; n = 58) vs. high-speed rotational atherectomy (ROTA; n = 61) for the treatment of in-stent restenosis of native coronary arteries. There were no in-hospital deaths, Q-wave myocardial infarctions, or emergency coronary artery bypass surgery in either group. DCA resulted in a larger postprocedural minimal luminal diameter of (2.57 +/- 0.51 vs. 2.14 +/- 0.37 mm; P < 0.0001) and a larger acute gain (1.83 +/- 0.52 vs. 1.42 +/- 0.48 mm; P < 0.0001). Furthermore, 12-month clinically indicated target lesion revascularization (39% vs. 21%; P = 0.02) and long-term follow-up MACE (44% vs. 28%; P = 0.03) was greater in the ROTA group. The present study suggests that DCA appears to be superior to ROTA for the treatment of in-stent restenosis of native coronary arteries. Compared to ROTA, the debulking effect of DCA leads to a larger postprocedure minimal luminal diameter, and a lower incidence of subsequent target lesion revascularization and MACE.

Percutaneous transcatheter closure of patent foramen ovale in patients with paradoxical embolism.

BACKGROUND: Percutaneous transcatheter closure of patent foramen ovale (PFO) is used as an alternative to surgery or long-term anticoagulation for the treatment of patients with paradoxical embolism and PFO. METHODS AND RESULTS: We report the immediate and long-term clinical and echocardiographic outcome of 110 consecutive patients (58 males, mean age 47+/-14 years) who underwent transcatheter closure of PFO because of paradoxical embolism between 1995 and 2001. Procedural success, defined as successful deployment of the device and effective occlusion (no, or trivial, shunt after device placement), was achieved in all (100%) patients. There was no in-hospital mortality, 1 device migration requiring surgical intervention (0.9%), and 1 episode of cardiac tamponade (0.9%) requiring pericardiocentesis. A progressive increment in full occlusion was observed (44%, 51%, 66%, and 71% at 1 day, 6 months, and 1 and 2 years, respectively, after device placement). At a mean follow-up of 2.3 years, 2 patients experienced recurrent neurological events (1 fatal stroke and 1 transient ischemic attack), representing an annual risk of recurrence of 0.9%. In addition, 4 (3.6%) of the patients required reintervention for device malalignment or significant shunt. Kaplan-Meier analysis showed a freedom from recurrent embolic events and reintervention of 96% and 90% at 1 and 5 years, respectively. CONCLUSIONS: Transcatheter closure of PFO is a safe and effective therapy for patients with paradoxical embolism and PFO. It is associated with a high success rate, low incidence of hospital complications, and low frequency of recurrent systemic embolic events.

A novel pulsatile, laminar flow bioreactor for the development of tissue-engineered vascular structures.

Exposure of vascular cell-seeded, tubular, biodegradable polymers to pulsatile flow conditions has been proposed as a method to develop tissue-engineered blood vessels by "maturing" structural integrity, and increasing collagen content, suture retention, burst pressure, and tissue formation. These in vitro tissue-engineered arteries demonstrate contractile responses to pharmacologic agents and express markers of vascular differentiation. Current methods to induce pulsatile flow in a bioreactor system are limited by the creation of nonphysiologic pressure waveforms and noncompliant reservoirs to house the tissue-engineered vascular constructs. We have developed a novel method for the in vitro development of tubular vascular structures by using a mechanical ventilator to induce pulsatile, laminar flow into a fluid column, resulting in pressurized waveforms similar to mammalian physiology. The vascular constructs are housed in semicompliant tubing to facilitate an additional variable of circumferential stretch as a potential signaling mechanism. This approach more closely approximates mammalian physiology and we hypothesize that it will facilitate mechanical signaling necessary for the development of tissue-engineered vessels for clinical applications.