Safety and feasibility of zero-contrast transcatheter aortic valve implantation using balloon-expandable valves in patients with aortic stenosis and severe renal impairment: A single-center study.

BACKGROUND: Aortic stenosis (AS) and chronic kidney disease (CKD) can coexist. Repeat exposure to contrast media in patients undergoing transcatheter aortic valve implantation (TAVI) has latent mortality risks and increased risk for acute kidney injury. We aimed to assess our "zero-contrast TAVI" protocol for patients with advanced CKD. METHODS: Consecutive patients with severe AS who underwent TAVI at a single center registry were enrolled. Zero-contrast TAVI group included patients who underwent TAVI without contrast and who had an estimated glomerular filtration rate <30 mL/min/1.73 m2. Conventional TAVI group included patients who underwent the regular TAVI procedure. Patients using balloon-expandable valves via transfemoral approach were analyzed. Baseline clinical and procedural characteristics and clinical outcomes were compared between two groups. The primary outcome was early safety as defined by Valve Academic Research Consortium Criteria. Secondary outcomes included the presence of severe prosthesis-patient mismatch, moderate or greater perivalvular leakage, and requirement for new dialysis (within 3 months). RESULTS: A total of 520 patients were analyzed. Among these, 32 (6 %) underwent zero-contrast TAVI and 488 (94 %) conventional TAVI. In the zero-contrast TAVI group, 12 patients (37.5 %) had to use 20.7 (11.0-31.2) mL of contrast media. There were no significant differences in the primary and secondary outcomes between zero-contrast TAVI and conventional TAVI groups (78.1 % vs. 86.8 %, P = 0.184 and 9.4 % vs. 8.1 %, P = 0.738 for the primary and secondary outcomes, respectively). CONCLUSIONS: Zero-contrast TAVI is feasible, safe, and effective in patients with AS and stage 4 CKD.

Prevalence and Clinical Outcomes of Noncardiac Surgery After Transcatheter Aortic Valve Replacement.

Aortic stenosis is a prevalent valvular heart disease, especially in the older people. They often coexist with other co-morbidities, and noncardiac surgery carries a higher risk because of the underlying valve condition. Despite the growing concern about the safety and optimal management of noncardiac surgery post-transcatheter aortic valve replacement (TAVR), there is limited evidence on this matter. This study aims to assess the clinical outcomes of noncardiac surgeries after TAVR. This retrospective study included 718 patients who underwent TAVR. Of these, 36 patients underwent noncardiac surgery after TAVR. The primary end point was the incidence of cardiovascular adverse events post-TAVR and the secondary end point was the incidence of structural valve deterioration. Composite end points included disabling stroke, heart failure requiring hospitalization, and cardiac death as defined by Valve Academic Research Consortium 3. Most of these surgeries were orthopedic and classified as intermediate risk. All noncardiac surgeries were performed without perioperative adverse events. There was no observed structural valve deterioration, and the incidence of composite end points did not significantly differ between the surgical and nonsurgical groups during the follow-up period. Noncardiac surgery after TAVR can be performed safely and does not have a negative impact on prognosis. Further studies are warranted to determine the optimal strategy for noncardiac surgery after TAVR.

Feasibility of Transcatheter Aortic Valve Implantation in Patients With Very Severe Aortic Stenosis.

Background: Very severe aortic stenosis (AS) has a poor prognosis even in asymptomatic patients, and asymptomatic very severe AS is a Class IIa indication for aortic valve replacement, although the safety and effectiveness of transcatheter aortic valve implantation (TAVI) for very severe AS is not well-established. Methods and Results: This study included 366 patients undergoing TAVI at a single center, with 85 and 281 patients in the very severe AS (peak velocity ≥5 m/s or mean pressure gradient (PG) ≥60 mmHg) and severe AS groups, respectively. Procedural and clinical outcomes at 1-year follow-up were compared between groups. The calcium scores were significantly higher in the very severe AS group (2,864.5 vs. 1,405.8 arbitrary units [AU] (P<0.001). Although the patient-prosthesis mismatch rate was higher in the very severe AS group (38.3% vs. 25.7%; P=0.029), there was no significant difference in the early safety and clinical efficacy between the groups (16.5% vs. 17.1% and 12.0% vs. 18.9%, respectively). Similarly, there was no significant difference in all-cause mortality at 1 year (4.8% vs. 9.8%). Conclusions: Despite a higher incidence of prosthesis-patient mismatch in those with very severe AS, the procedural and clinical outcomes were comparable to those in patients with severe AS. TAVI may be a reasonable treatment option for very severe AS.

Large ovarian tumor-caused failure of VA-ECMO in a patient with cardiac arrest related to massive pulmonary embolism.

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) plays an important role in patients with massive pulmonary embolism (PE)-related cardiac arrest. A 47-year-old healthy Japanese woman was brought to the emergency department because of shock. The patient suddenly collapsed due to cardiac arrest in an ambulance. The patient was diagnosed with PE on transthoracic echocardiography during cardiopulmonary resuscitation (CPR). Emergency VA-ECMO cannulation was performed percutaneously. Although VA-ECMO support was initiated, the return cannula flow could not be pumped because of the high resistance. Circulation support with VA-ECMO was discontinued. Subsequently, pulmonary angiography under CPR revealed numerous thrombi in the bilateral pulmonary arteries, and aspiration thrombectomy and catheter fragmentation were performed. The patient achieved spontaneous recovery of circulation after successful catheter fragmentation. After the procedure to investigate the cause of VA-ECMO failure, whole-body computed tomography showed a large ovarian tumor and compression of the femoral artery and abdominal aorta. The patient died of multiple organ failure due to hypoxic encephalopathy. Undiagnosed gynecological tumors often cause fulminant PE and may also cause the failure of VA-ECMO due to vascular compression. Alternative cannulation sites and prior thrombolysis should be immediately considered. The complexity of PE management necessitates a well-trained PE response team. Learning objective: Large gynecological tumors may cause pulmonary embolism-related cardiac arrest and consequent failure of venoarterial extracorporeal membrane oxygenation using the femoral artery approach due to vascular compression by the tumor. An adequate strategy should be considered to achieve immediate recovery of spontaneous circulation and circulation support as simultaneous systematic thrombolysis and an alternative central cannulation approach to protect against hypoxic organ damage. The complexity of pulmonary embolism (PE) management necessitates a well-trained PE response team.