Aortic valve disorders and left ventricular assist devices.

Aortic valve disorders are important considerations in advanced heart failure patients being evaluated for left ventricular assist devices (LVAD) and those on LVAD support. Aortic insufficiency (AI) can be present prior to LVAD implantation or develop de novo during LVAD support. It is usually a progressive disorder and can lead to impaired LVAD effectiveness and heart failure symptoms. Severe AI is associated with worsening hemodynamics, increased hospitalizations, and decreased survival in LVAD patients. Diagnosis is made with echocardiographic, device assessment, and/or catheterization studies. Standard echocardiographic criteria for AI are insufficient for accurate diagnosis of AI severity. Management of pre-existing AI includes aortic repair or replacement at the time of LVAD implant. Management of de novo AI on LVAD support is challenging with increased risks of repeat surgical intervention, and percutaneous techniques including transcatheter aortic valve replacement are assuming greater importance. In this manuscript, we provide a comprehensive approach to contemporary diagnosis and management of aortic valve disorders in the setting of LVAD therapy.

Early Experience with the HeartMate Percutaneous Heart Pump from the SHIELD II Trial.

The HeartMate Percutaneous Heart Pump (PHP) is a novel circulatory support catheter delivering a self-expanding 24 French impeller across the aortic valve. The SHIELD II trial compares outcomes among heart failure patients undergoing high-risk percutaneous coronary intervention (HR-PCI) with the PHP versus Impella systems. The trial was halted in 2017 due to device malfunctions. We aimed to describe procedural, hemodynamic, and clinical outcomes among HR-PCI patients treated with PHP as part of the SHIELD II trial roll-in phase. Procedural, hemodynamic, and 90 day outcomes were assessed among patients undergoing HR-PCI with a left ventricular ejection fraction ≤35% and last patent coronary conduit, unprotected left main disease, or significant three vessel disease. The primary endpoint was the 90 day composite of cardiovascular death, myocardial infarction, stroke, repeat revascularization, major bleeding, new/worsening aortic regurgitation, and severe hypotension. Among 75 roll-in phase patients, PHP support duration was 101 ± 53 minutes with 2.5 ± 1.4 coronary lesions treated per patient. Compared with predevice values, the PHP system increased cardiac power and mean arterial pressure. Maximum recorded device flows were 0.4-6.2 L/minute with 26% (n = 19/73) and 9.6% (n = 7/73) of patients achieving peak flows above 3.5 or 5.0 L/minute, respectively. Five PHP device malfunction events (6.7%) were observed. At 90 days, the composite endpoint occurred in 24.3% (18/74) of patients. Early PHP experience demonstrated successful device performance in the majority of enrolled patients; however, unexpected malfunctions led to device revision. Completion of the SHIELD II trial will be required to confirm the safety and efficacy of this iteration of the PHP system in HR-PCI.

Percutaneous Axillary Access for Placement of Microaxial Ventricular Support Devices: The Axillary Access Registry to Monitor Safety (ARMS).

BACKGROUND: There has been increasing utilization of short-term mechanical circulatory support devices for a variety of clinical indications. Many patients have suboptimal iliofemoral access options or reasons why early mobilization is desirable. Axillary artery access is an option for these patients, but little is known about the utility of this approach to facilitate short-term use for circulatory support with microaxial pump devices. METHODS: The Axillary Access Registry to Monitor Safety (ARMS) was a prospective, observational multicenter registry to study the feasibility and acute safety of mechanical circulatory support via percutaneous upper-extremity access. RESULTS: One hundred and two patients were collected from 10 participating centers. Successful device implantation was 98% (100 of 102). Devices were implanted for a median of 2 days (interquartile range, 0-5 days; range, 0-35 days). Procedural complications included 10 bleeding events and 1 stroke. There were 3 patients with brachial plexus-related symptoms all consisting of C8 tingling and all arising after multiple days of support. Postprocedural access site hematoma or bleeding was noted in 9 patients. Device explantation utilized closure devices alone in 61%, stent grafts in 17%, balloon tamponade facilitated closure in 15%, and planned surgical explant in 5%. Duration of support appeared to be independently associated with a 1.1% increased odds of vascular complication per day ([95% CI, 0.0%-2.3%] P=0.05). CONCLUSIONS: Percutaneous axillary access for use with microaxial support pumps appears feasible with acceptable rates of bleeding despite early experience. Larger studies are necessary to confirm the pilot data presented here.

Randomized Pilot Clinical Trial of Early Coronary Angiography Versus No Early Coronary Angiography After Cardiac Arrest Without ST-Segment Elevation: The PEARL Study.

BACKGROUND: The benefit of emergency coronary angiography after resuscitation from out-of-hospital cardiac arrest is uncertain for patients without ST-segment elevation. The aim of this randomized trial was to evaluate the efficacy and safety of early coronary angiography and to determine the prevalence of acute coronary occlusion in resuscitated patients with out-of-hospital cardiac arrest without ST-segment elevation. METHODS: Adult (>18 years) comatose survivors without ST-segment elevation after resuscitation from out-of-hospital cardiac arrest were prospectively randomized in a 1:1 fashion under exception to informed consent regulations to early coronary angiography versus no early coronary angiography in this multicenter study. Early angiography was defined as ≤120 minutes from arrival at the percutaneous coronary intervention-capable facility. The primary end point was a composite of efficacy and safety measures, including efficacy measures of survival to discharge, favorable neurologic status at discharge (Cerebral Performance Category score ≤2), echocardiographic measures of left ventricular ejection fraction >50%, and a normal regional wall motion score of 16 within 24 hours of admission. Adverse events included rearrest, pulmonary edema on chest x-ray, acute renal dysfunction, bleeding requiring transfusion or intervention, hypotension (systolic arterial pressure ≤90 mm Hg), and pneumonia. Secondary end points included the incidence of culprit vessels with acute occlusion. RESULTS: The study was terminated prematurely before enrolling the target number of patients. A total of 99 patients were enrolled from 2015 to 2018, including 75 with initially shockable rhythms. Forty-nine patients were randomized to early coronary angiography. The primary end point of efficacy and safety was not different between the 2 groups (55.1% versus 46.0%; P=0.64). Early coronary angiography was not associated with any significant increase in survival (55.1% versus 48.0%; P=0.55) or adverse events (26.5% versus 26.0%; P=1.00). Early coronary angiography revealed a culprit vessel in 47%, with a total of 14% of patients undergoing early coronary angiography having an acutely occluded culprit coronary artery. CONCLUSIONS: This underpowered study, when considered together with previous clinical trials, does not support early coronary angiography for comatose survivors of cardiac arrest without ST elevation. Whether early detection of occluded potential culprit arteries leads to interventions that improve outcomes requires additional study. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02387398.

Predicting paravalvular leak after transcatheter mitral valve replacement using commercially available software modeling.

BACKGROUND: There is limited data identifying patients at risk for significant mitral regurgitation (MR) after transcatheter mitral valve replacement (TMVR). We hypothesized that software modeling based on computed tomography angiography (CTA) can predict the risk of moderate or severe MR after TMVR. METHODS: 58 consecutive patients underwent TMVR at two institutions, including 31 valve-in-valve, 16 valve-in-ring, and 11 valve-in-mitral annular calcification. 12 (20%) patients developed moderate or severe MR due to paravalvular leak (PVL). RESULTS: The software model correctly predicted 8 (67%) patients with significant PVL, resulting in sensitivity of 67%, specificity 96%, positive predictive value 89%, and negative predictive value 86%. There was excellent agreement between CTA readers using software modeling to predict PVL (kappa 0.92; p < 0.01). On univariate analysis, CTA predictors of moderate or severe PVL included presence of a gap between the virtual valve and mitral annulus on the software model (OR 48; p < 0.01), mitral annular area (OR 1.02; p 0.01), and % valve oversizing (OR 0.9; p 0.01). On multivariate analysis, only presence of a gap on the software model remained significant (OR 36.8; p < 0.01). CONCLUSIONS: Software modeling using pre-procedural CTA is a straightforward method for predicting the risk of moderate and severe MR due to PVL after TMVR.

Arrhythmias in Relation to Mortality After Transcatheter Aortic Valve Replacement.

BACKGROUND: The purpose of this study was to identify predictors of mortality and potentially modifiable factors related to arrhythmias in patients that undergo transcatheter aortic valve replacement (TAVR). Patients that undergo TAVR are at risk for complete heart block requiring pacemaker implant. Additionally, other arrhythmias, specifically atrial fibrillation (AF), are common in this population. It is unclear how arrhythmias and their management contribute to mortality risk. METHODS: The study analyzed 176 patients who underwent TAVR at a single center. Factors associated with pacemaker implantation within 30 days were analyzed by logistic regression. Factors associated with mortality were analyzed by Kaplan-Meier and Cox regression analyses. RESULTS: Mean age was 80 ± 8.5 years. AF was present in 69 patients, and 39 received anticoagulation. Post-TAVR, a pacemaker was implanted in 25 patients within 30 days. Over a follow up of 566 ± 496 days, 49 patients died. In multivariable analysis, right bundle branch block remained significant (odds ratio 4.212, P = 0.012) for pacemaker implant within 30 days. The AF (hazard ratio [HR] 3.905, P = 0.001), albumin level (HR 0.316, P = 0.034), and diabetes (HR 2.323, P = 0.027) were predictors of death in a multivariate analysis, while pacemaker implant within 30 days was not. Patients with AF who were anticoagulated had improved survival in a stratified Kaplan-Meier analysis compared with those who were not anticoagulated (P = 0.0001). CONCLUSION: AF, diabetes, and low albumin levels are independently associated with mortality after TAVR. In particular, patients with AF who are not anticoagulated are at highest risk for death. Efforts to identify AF and consider anticoagulation should be emphasized.

Extracorporeal Membrane Oxygenation as a Bridge to Durable Mechanical Circulatory Support: An Analysis of the STS-INTERMACS Database.

BACKGROUND: Limited data are available regarding the outcomes of patients supported by extracorporeal membrane oxygenation (ECMO) who undergo durable mechanical circulatory support implantation (dMCS). We analyzed the clinical characteristics, outcomes, and risk factors for mortality in patients who were bridged with ECMO to dMCS. METHODS: Adult patients who received dMCS between January 2008 and December 2017 (n=19 824), registered in the Society of Thoracic Surgeons-Interagency Registry for Mechanical Assisted Circulatory Support (STS-INTERMACS) database were included. Baseline characteristics, outcomes, risk factors, and adverse events were compared between ECMO-supported patients (n=933) and INTERMACS profile 1 (IP-1) patients not supported by ECMO (n=2362). A propensity match analysis was performed. RESULTS: ECMO patients had inferior survival at 12 months (66.1%) than non-ECMO patients (75.4%; P<0.0001). The proportion of patients transplanted at 2 years after dMCS was similar between the ECMO (30.8%) and non-ECMO (31.8%) groups (P=0.49). A multiphase parametric hazard model identified 2 different periods based on risk of death. ECMO patients had a high hazard for death in the first 6 months after implantation (hazard ratio, 2.18 [1.79-2.66]; P<0.001). Multivariable analysis showed that ECMO was an independent risk factor associated with poor outcome during the early phase after dMCS (hazard ratio, 1.69 [1.37-2.09]; P<0.0001) but not during the constant phase. ECMO patients had similar outcomes to non-ECMO patients when a propensity matched cohort was analyzed. CONCLUSIONS: ECMO-supported patients before dMCS have lower survival compared with other IP-1 patients. A multivariable analysis showed that ECMO is an independent risk factor of poor outcome after dMCS. However, a propensity matched analysis suggested that when important clinical variables are controlled the outcome of both groups is similar. These data support the implantation of dMCS in carefully selected ECMO patients.

Degenerated TAVR Within Degenerated Surgical Bioprosthetic Valve Treated With Second TAVR.

Transcatheter aortic valve replacement within a degenerated surgical bioprosthetic aortic valve is increasing in frequency. We present a rare case of a patient requiring a second TAVR placed within a previous placed degenerated transcatheter aortic valve, which was implanted in a degenerated surgical bioprosthetic aortic valve. (Level of Difficulty: Advanced.).

Novel technique of performing multivessel PCI through an Impella sheath.

A 69-year-old woman with diabetes was found to have multi-vessel coronary artery disease and underwent 5-vessel coronary artery bypass grafting. Patient had persistent cardiogenic shock postoperatively despite intra-aortic balloon pump and escalating pressor requirements. Electrocardiogram showed new ischemic changes and the patient was urgently taken to the catheterization lab for coronary angiography and placement of an Impella CP for higher degree of hemodynamic support via the left femoral artery. Due to limitations in vascular access the Impella CP sheath was utilized for vascular access for diagnostic angiography and coronary intervention concurrently with ongoing Impella CP support. The first obtuse marginal had severe proximal disease and was treated with percutaneous coronary intervention (PCI) with a drug eluting stent. To our knowledge, this case is the first in which successful diagnostic angiography as well as multi-vessel PCI was performed via an Impella sheath while concurrently using the percutaneous mechanical circulatory support system of the Impella CP. Multiple guide catheters and a pigtail catheter were successfully passed via the Impella CP sheath to perform PCI. This novel method of vascular access could be an important tool to use in high-risk patients with limitations in access sites and decrease potential bleeding complications by limiting the number of arterial punctures.

Cardiac Arrest in the Cardiac Catheterization Laboratory: Combining Mechanical Chest Compressions and Percutaneous LV Assistance.

OBJECTIVES: The aim of this study was to evaluate the optimal treatment approach for cardiac arrest (CA) occurring in the cardiac catheterization laboratory. BACKGROUND: CA can occur in the cath lab during high-risk percutaneous coronary intervention. While attempting to correct the precipitating cause of CA, several options are available to maintain vital organ perfusion. These include manual chest compressions, mechanical chest compressions, or a percutaneous left ventricular assist device. METHODS: Eighty swine (58 ± 10 kg) were studied. The left main or proximal left anterior descending artery was occluded. Ventricular fibrillation (VFCA) was induced and circulatory support was provided with 1 of 4 techniques: either manual chest compressions (frequently interrupted), mechanical chest compressions with a piston device (LUCAS-2), an Impella 2.5 L percutaneously placed LVAD, or the combination of mechanical chest compressions and the percutaneous left ventricular assist device. The study protocol included 12 min of left main coronary occlusion, reperfusion, with defibrillation attempted after 15 min of VFCA. Primary outcome was favorable neurological function (CPC 1 or 2) at 24 h, while secondary outcomes included return of spontaneous circulation and hemodynamics. RESULTS: Manual chest compressions provided fewer neurologically intact surviving animals than the combination of a mechanical chest compressor and a percutaneous LVAD device (0% vs. 56%; p < 0.01), while no difference was found between the 2 mechanical approaches (28% vs. 35%: p = 0.75). Comparing integrated coronary perfusion pressure showed sequential improvement in hemodynamic support with mechanical devices (401 ± 230 vs. 1,337 ± 905 mm Hg/s; p = 0.06). CONCLUSIONS: Combining 2 mechanical devices provided superior 24-h survival with favorable neurological recovery compared with manual compressions during moderate duration VFCA associated with an acute coronary occlusion in the animal catheterization laboratory.

Drug-coated balloon in peripheral artery disease.

Peripheral artery disease (PAD) is highly prevalent but is often underdiagnosed and undertreated. Lower extremity PAD can often be life style limiting. Revascularization in carefully selected lower extremity PAD patients improves symptoms and functional status. Surgical revascularization used to be the only available strategy, but in the recent years, endovascular strategies have gained popularity due to faster recovery times with low morbidity and mortality rates. Endovascular procedures have increased significantly in the United States in the past few years. That being said, higher restenosis rates and low long-term patency rates have been the limiting factors for this strategy. Drug eluting stents have been introduced to help with lowering restenosis, however lower extremity PAD involves long segment where the outcomes of stents are suboptimal. Also, the disease often crosses joint line that makes it less ideal for the stents. Drug-coated balloons (DCB) have been introduced to improve patency rates following endovascular intervention for lower extremity PAD. They have gained popularity among endovascular specialists due to its ease of use and the concept of "leave nothing behind". This is a review of scientific evidence supporting DCB use in PAD.

Prophylactic Left Ventricular Outflow Tract Septal Ablation Before Transcatheter Mitral Valve Replacement.

An 82-year-old woman with severe respiratory distress and limitations in functional status was found to have severe mitral valve stenosis with annular calcification and referred for transcatheter mitral valve replacement. Prophylactic alcohol septal ablation was used pre-procedurally to minimize mortality risk due to obstruction of the left ventricular outflow tract. (Level of Difficulty: Intermediate.).

Unloading the Left Ventricle Before Reperfusion in Patients With Anterior ST-Segment-Elevation Myocardial Infarction.

BACKGROUND: In ST-segment-elevation myocardial infarction (STEMI), infarct size correlates directly with heart failure and mortality. Preclinical testing has shown that, in comparison with reperfusion alone, mechanically unloading the left ventricle (LV) before reperfusion reduces infarct size and that 30 minutes of unloading activates a cardioprotective program that limits reperfusion injury. The DTU-STEMI pilot trial (Door-To-Unload in STEMI Pilot Trial) represents the first exploratory study testing whether LV unloading and delayed reperfusion in patients with STEMI without cardiogenic shock is safe and feasible. METHODS: In a multicenter, prospective, randomized exploratory safety and feasibility trial, we assigned 50 patients with anterior STEMI to LV unloading by using the Impella CP followed by immediate reperfusion (U-IR) versus delayed reperfusion after 30 minutes of unloading (U-DR). The primary safety outcome was a composite of major adverse cardiovascular and cerebrovascular events at 30 days. Efficacy parameters included the assessment of infarct size by using cardiac magnetic resonance imaging. RESULTS: All patients completed the U-IR (n=25) or U-DR (n=25) protocols with respective mean door-to-balloon times of 72 versus 97 minutes. Major adverse cardiovascular and cerebrovascular event rates were not statistically different between the U-IR versus U-DR groups (8% versus 12%, respectively, P=0.99). In comparison with the U-IR group, delaying reperfusion in the U-DR group did not affect 30-day mean infarct size measured as a percentage of LV mass (15±12% versus 13±11%, U-IR versus U-DR, P=0.53). CONCLUSIONS: We report that LV unloading using the Impella CP device with a 30-minute delay before reperfusion is feasible within a relatively short time period in anterior STEMI. The DTU-STEMI pilot trial did not identify prohibitive safety signals that would preclude proceeding to a larger pivotal study of LV unloading before reperfusion. An appropriately powered pivotal trial comparing LV unloading before reperfusion to the current standard of care is required. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03000270.

Refractory Out of Hospital Cardiac Arrest.

Refractory out of hospital cardiac arrest is a common problem that is associated with poor overall survival rates and neurological outcomes. There are various definitions that have been used but the most accepted one is cardiac arrest that requires more than 10 minutes of Cardiopulmonary Resuscitation (CPR) efforts or more than 3 defibrillation attempts. There have been different pharmacologic and non-pharmacologic therapies that were studied in these patients. None of the antiarrhythmic or vasopressor medications have been consistently shown to improve survival or neurological outcomes in this subset of patients. This has led to the introduction of various devices aimed at improving outcomes such as mechanical CPR devices, Extracorporeal Cardiopulmonary Resuscitation (ECPR), targeted temperature management and early invasive approach. There is accumulating evidence that there seems to be an improvement in outcomes when these devices are used in refractory cardiac arrest patients. But none of these devices have been shown to improve outcomes when used in isolation. This underscores the importance of systematic approach to these complex patients and using these therapies in combination. There has been a paradigm shift in the approach to these patients. Instead of repeated and prolonged CPR attempts in the field, it is suggested that these patients need to be moved to cardiac arrest centers with a mechanical CPR device in place, so a percutaneous Extracorporeal Membrane Oxygenator (ECMO) can be placed to "buy" time for other therapies such as therapeutic hypothermia and early coronary angiography followed by intervention as indicated. Careful selection of patients who might potentially benefit from this approach is critical to the success of these programs.

Insertion of the Impella via the axillary artery for high-risk percutaneous coronary intervention.

Hemodynamic support with the Impella device is an important tool during high risk percutaneous coronary intervention. This device is usually inserted via the femoral artery. However, some patients have severe peripheral artery disease precluding the use of the femoral artery for this purpose. The axillary artery is a viable alternative in these cases. We reviewed the two access techniques for inserting the Impella via the axillary artery and also described 6 cases of successful implantation.

Mitral valve replacement complicated by iatrogenic left ventricular outflow obstruction and paravalvular leak: case report and review of literature.

BACKGROUND: Left ventricular outflow tract (LVOT) obstruction and paravalvular leak (PVL) are relatively uncommon, but are serious complications of prosthetic valve replacement. CASE PRESENTATION: We present a case that displays the unique therapeutic challenges of treating a patient who developed both LVOT obstruction and mitral PVL after undergoing surgical aortic and mitral valve replacement (MVR). We also describe the use of alcohol septal ablation and albumin-glutaraldehyde (BioGlue) for septal ablation to percutaneously treat the patient's LVOT obstruction, followed by use of an Amplatzer vascular plug for percutaneous closure of an antero-medial mitral PVL associated with severe regurgitation. CONCLUSION: Percutaneous interventional management of these entities may be considered as an initial therapeutic option, especially in high-risk patients with significant morbidity and mortality of repeat surgical operations.

Prosthetic mitral valve obstruction: role of real-time three-dimensional transesophageal echocardiography in diagnosis.

Acute prosthetic valve thrombosis is a potentially serious complication with an incidence as high as 6% per patient-year for prostheses in the mitral position. Accurate diagnosis of the degree of obstruction and differentiation of pannus versus thrombus is critical in determination of the best mode of therapy. We discuss a case of a patient with multiple comorbidities who presented with mechanical mitral valve obstruction where both transthoracic and two-dimensional transesophageal echocardiography (TEE) were limited in making an accurate diagnosis regarding the mechanism of obstruction. Real-time 3D-TEE (RT-3DTEE) was critical in identifying a partial thrombus on the mechanical valve and guided the choice of thrombolysis as the most appropriate intervention, thus avoiding high-risk surgery in this patient with significant multiple comorbidities.

Outcomes of Comatose Cardiac Arrest Survivors With and Without ST-Segment Elevation Myocardial Infarction: Importance of Coronary Angiography.

OBJECTIVES: The aim of this study was to compare outcomes and coronary angiographic findings in post-cardiac arrest patients with and without ST-segment elevation myocardial infarction (STEMI). BACKGROUND: The 2013 STEMI guidelines recommend performing immediate angiography in resuscitated patients whose initial electrocardiogram shows STEMI. The optimal approach for those without STEMI post-cardiac arrest is less clear. METHODS: A retrospective evaluation of a post-cardiac arrest registry was performed. RESULTS: The database consisted of 746 comatose post-cardiac arrest patients including 198 with STEMI (26.5%) and 548 without STEMI (73.5%). Overall survival was greater in those with STEMI compared with those without (55.1% vs. 41.3%; p = 0.001), whereas in all patients who underwent immediate coronary angiography, survival was similar between those with and without STEMI (54.7% vs. 57.9%; p = 0.60). A culprit vessel was more frequently identified in those with STEMI, but also in one-third of patients without STEMI (80.2% vs. 33.2%; p = 0.001). The majority of culprit vessels were occluded (STEMI, 92.7%; no STEMI, 69.2%; p < 0.0001). An occluded culprit vessel was found in 74.3% of STEMI patients and in 22.9% of no STEMI patients. Among cardiac arrest survivors discharged from the hospital who had presented without STEMI, coronary angiography was associated with better functional outcome (93.3% vs. 78.7%; p < 0.003). CONCLUSIONS: Early coronary angiography is associated with improved functional outcome among resuscitated patients with and without STEMI. Resuscitated patients with a presumed cardiac etiology appear to benefit from immediate coronary angiography.