Clinical impact of baseline chronic kidney disease in patients undergoing transcatheter or surgical aortic valve replacement

ObjectivesTo assess the treatment effect of TAVR versus SAVR on clinical outcomes to 3 years in patients stratified by chronic kidney disease (CKD) by retrospectively studying patients randomized to TAVR or SAVR.BackgroundThe impact of CKD on mid‐term outcomes of patients undergoing TAVR versus SAVR is unclear.MethodsPatients randomized to TAVR or SAVR in the CoreValve US Pivotal High Risk Trial were retrospectively stratified by eGFR: none/mild or moderate/severe CKD. To evaluate the impact of baseline CKD in TAVR patients only, all patients undergoing an attempted TAVR implant in the US Pivotal Trial and CAS were stratified by baseline eGFR into none/mild, moderate, and severe CKD. The primary endpoint was major adverse cardiovascular and renal events (MACRE), a composite of all‐cause mortality, myocardial infarction, stroke/TIA, and new requirement of dialysis.ResultsModerate/severe CKD was present in 62.7% and 60.7% of high‐risk patients randomized to TAVR or SAVR, respectively. Baseline characteristics were similar between TAVR and SAVR patients in both CKD subgroups, except for higher rates of diabetes and higher serum creatinine in SAVR patients. Among high‐risk patients with moderate/severe CKD, TAVR provided a lower 3‐year MACRE rate compared with SAVR: 42.1% vs. 51.0, P = .04. Of 3,733 extreme‐ and high‐risk TAVR patients, 39.9% had none/mild, 53.8% moderate, and 6.4% severe CKD. Worsening baseline CKD was associated with increased 3‐year MACRE rates [none/mild 51.5%, moderate 54.5%, severe 63.1%, P = .001].ConclusionsTAVR results in lower 3‐year MACRE versus SAVR in high‐risk patients with moderate/severe CKD. In patients undergoing TAVR, worsening CKD increases mid‐term mortality and MACRE. Randomized trials of TAVR vs. SAVR in patients with moderate‐severe CKD would help elucidate the best treatment for these complex patients.Trial RegistrationCoreValve US Pivotal Trial: NCT01240902.CoreValve Continued Access Study: NCT01531374.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148361/1/ccd27928_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148361/2/ccd27928.pd

Valvuloplasty in woman with heterotaxy syndrome

BACKGROUND: Anatomic variations can make structural interventions challenging and require a more creative approach. Persistent left superior vena cava is an uncommon entity; even more uncommon is a left-sided inferior vena cava connecting to the persistent superior vena cava with eventual drainage to the coronary sinus. Heterotaxia is another twist on normal anatomy, and rarer still. CASE: A 77-year-old woman with chronic atrial fibrillation and New York Heart Association (NYHA) functional class III heart failure symptoms requiring supplemental oxygen underwent transthoracic echocardiography and was noted to have severe rheumatic mitral stenosis (resting mean gradient of 10 mmHg, valve area \u3c1 cm2 ), severe pulmonary hypertension and a severely dilated left atrium. Left heart catheterization showed no significant coronary artery disease. Right heart catheterization via a right femoral approach delineated a left-sided inferior vena cava that drained into a left-sided superior vena cava with drainage into the coronary sinus. Computed tomography showed heterotaxy syndrome: polysplenia, midline liver, right-sided stomach and left-sided inferior vena cava. Given her severe, symptomatic mitral stenosis, balloon valvuloplasty was needed. DECISION‐MAKING: Traditionally, mitral balloon valvuloplasty is performed via a transseptal approach. Given her uncharacteristic vascular anatomy, this was deemed high risk. Prior accounts of mitral interventions via a transapical approach have been described, and this approach was deemed a safer method in this case. Therefore, under transesophageal and fluoroscopic guidance, she underwent mitral valvuloplasty via a transapical route. Multiple balloon inflations were performed successfully; her postprocedure gradient was only 5 mmHg, her heart failure symptoms improved to NYHA class I, and she was weaned from supplemental oxygen. CONCLUSIONS: This case illustrates unconventional anatomical variations, rarely encountered as individual entities, let alone in the same patient. Structural interventions, as described in this case, can still be safely undertaken with careful planning and consideration for alternative approaches

Transthoracic echocardiography is adequate for intraprocedural guidance of transcatheter aortic valve implantation

Background: While transcatheter aortic valve implantation (TAVI) has traditionally been supported intraprocedurally by transoesophageal echocardiography (TOE), transthoracic echocardiography (TTE) is increasingly being used. We evaluated echocardiographic imaging characteristics and clinical outcomes in patients who underwent TTE during TAVI (TTE-TAVI). Methods and results: A select team of dedicated sonographers and interventional echocardiographers performed TTE-TAVI in 278 patients, all of whom underwent TAVI through transfemoral access. We implanted the Medtronic EVOLUT R valve in 258 patients (92.8%). TTE images were acquired immediately pre-procedure by a dedicated sonographer in the cardiac catheterization laboratory with the patient in the supine position. TTE was then performed post deployment of TAVI. In the procedure, TTE image quality was fair or better in 249 (89.6%) cases. Color-flow Doppler was adequate or better in 275 (98.9%) cases. In 2 cases, paravalvular regurgitation (PVL) could not be assessed confidently by echocardiography due to poor image quality; in those cases, PVL was assessed by fluoroscopy, aortic root injection and invasive hemodynamics. Both TTE and invasive hemodynamics were used in the assessment of need for post-deployment stent ballooning (n = 23, 8.3%). TTE adequately recognized new pericardial effusion in 3 cases. No case required TOE conversion for image quality. There was only 1 case of intraprocedural TTE failing to recognize moderate PVL, without clinical implication. In 99% of patients, TTE-TAVI adequately assessed PVL compared with 24-h and 1-month follow-up TTE. Conclusions: With the current generation of TAVI, TTE-TAVI is adequate intraprocedurally when performed by specialized sonographers and dedicated cardiologists in a highly experienced TAVI center

Impact of annular and supra-annular CoreValve deployment locations on aortic and coronary artery hemodynamics

CoreValve is widely used in transcatheter aortic valve replacement, but the impact of its deployment location on hemodynamics is unexplored despite a potential role in subsequent aortic and coronary artery pathologies. The objectives of this investigation were to perform fluid-structure interaction (FSI) simulations for a 29 mm CoreValve deployed in annular vs supra-annular locations, and characterize resulting hemodynamics including velocity and wall shear stress (WSS). Patient-specific geometry was reconstructed from computed tomography scans and CoreValve was deployed using a finite element approach. FSI simulations were then performed using a boundary conforming method and realistic boundary conditions. Results showed that CoreValve deployment location impacts hemodynamics in the ascending aorta and flow patterns in the coronary arteries. During peak-systole, annularly deployed CoreValve produced a jet-like flow structure impinging on the outer-curvature of the ascending aorta. Supra-annularly deployed CoreValve having a lateral tilt of 10° led to a more centered jet impinging further downstream. At mid-systole, valve leaflets of the annularly deployed CoreValve closed asymmetrically leading to disorganized flow patterns in the ascending aorta vs those from the supra-annular position. Supra-annularly deployed CoreValve also led to high-velocity para-valvular flow supplying the coronary arteries. CoreValve in the supra-annular position significantly (P < 0.05) elevated WSS within the first few diameters of both coronary arteries as compared to the annular position for many time points quantified. These results afforded by the advanced simulation methods may have important clinical implications given the role of aortic hemodynamics in dilation and the pro-atherogenic nature of WSS alterations in the coronary arteries

Seleniranium Ions Undergo π‑Ligand Exchange via an Associative Mechanism in the Gas Phase

Collision-induced dissociation mass spectrometry of the ammonium ions <b>4a</b> and <b>4b</b> results in the formation of the seleniranium ion <b>5</b>, the structure and purity of which were verified using gas-phase infrared spectroscopy coupled to mass spectrometry and gas-phase ion-mobility measurements. Ion–molecule reactions between the ion <b>5</b> (<i>m</i>/<i>z</i> = 261) and cyclopentene, cyclohexene, cycloheptene, and cyclooctene resulted in the formation of the seleniranium ions <b>7</b> (<i>m</i>/<i>z</i> = 225), <b>6</b> (<i>m</i>/<i>z</i> = 239), <b>8</b> (<i>m</i>/<i>z</i> = 253), and <b>9</b> (<i>m</i>/<i>z</i> = 267), respectively. Further reaction of seleniranium <b>6</b> with cyclopentene resulted in further π-ligand exchange giving seleniranium ion <b>7</b>, confirming that direct π-ligand exchange between seleniranium ion <b>5</b> and cycloalkenes occurs in the gas phase. Pseudo-first-order kinetics established relative reaction efficiencies for π-ligand exchange for cyclopentene, cyclohexene, cycloheptene. and cyclooctene as 0.20, 0.07, 0.43, and 4.32. respectively. DFT calculations at the M06/6-31+G­(d) level of theory provide the following insights into the mechanism of the π-ligand exchange reactions; the cycloalkene forms a complex with the seleniranium ion <b>5</b> with binding energies of 57 and 62 kJ/mol for cyclopentene and cyclohexene, respectively, with transition states for π-ligand exchange having barriers of 17.8 and 19.3 kJ/mol for cyclopentene and cyclohexene, respectively