Long-term follow-up of balloon-expandable valves according to the implantation strategy: insight from the DIRECTAVI trial

BACKGROUND

Safety and feasibility of transcatheter aortic valve replacement (TAVR) without balloon aortic valvuloplasty (BAV) using the SAPIEN 3 balloon-expandable device has been previously demonstrated. The impact on long-term valve hemodynamic performances and outcomes remains however unknown. We evaluate long-term clinical and hemodynamic results according to the implant strategy (direct TAVR vs BAV pre-TAVR) in patients included in the DIRECTAVI randomized trial (NCT02729519).

METHODS

Clinical and echocardiographic follow-up until January 2023 was performed for all patients included in the DIRECTAVI trial since 2016 (n = 228). The primary endpoint was incidence of moderate/severe hemodynamic valve deterioration (HVD), according to the Valve Academic Research defined Consortium-3 criteria (increase in mean gradient ≥10 mmHg resulting in a final mean gradient ≥20 mmHg, or new/worsening aortic regurgitation of 1 grade resulting in ≥ moderate aortic regurgitation).

RESULTS

Median follow-up was 3.8 (2.2-4.7) years. Mean age at follow-up was 87 ± 6.7 years. No difference in incidence of HVD in the direct implantation group compared to the BAV group was found (incidence of 1.97 per 100 person-years and 1.45 per 100 person-years, respectively, P = 0.6). Prevalence of predicted prothesis-patient mismatch was low (n = 13 [11.4%] in the direct TAVR group vs n = 15 [13.2%] in BAV group) and similar between both groups (P = .7). Major outcomes including death, stroke, hospitalization for heart failure and pacemaker implantation were similar between both groups, (P = .4, P = .7, P = .3, and P = .3 respectively).

CONCLUSION

Direct implantation of the balloon-expandable device in TAVR was not associated with an increased risk of moderate/severe HVD or major outcomes up to 6-year follow-up. These results guarantee wide use of direct balloon-expandable valve implantation, when feasible.

CLINICAL TRIALS REGISTRATION NUMBER

NCT05140317.

Two-in-one: A case report of a touchy TAVI procedure with a new valve

Implantation of a second transcatheter heart valve (THV) into a primary THV is a bail-out situation, but may be necessary. An 85-year-old woman was referred with severe symptomatic aortic stenosis (AS). Echocardiography showed a moderately calcified AS. Computed tomography resulted in an average annular diameter of 22.3 mm and an area of 371 mm² , leading to M-sized ACURATE NEO implantation. Deployment of the upper valve part was uneventful. During lower valve part deployment, the valve dived into the left ventricle outflow tract with the stabilization arches above the annular plane. With the SAFARI guidewire in place, a second M-sized ACURATE NEO was implanted higher inside the first displaced valve. Deployment was straightforward, with no aortic leak, no mitral regurgitation and the patient had normal hemodynamic parameters. Follow-up was uneventful. Positioning a second ACURATE NEO into a failing primary ACURATE NEO is feasible and safe, with favorable short and longer-term outcome.

Optimizing pacemaker longevity with pacing mode and settings programming: results from a pacemaker multicenter registry

BACKGROUND

This study aimed to describe the influence on dual-chamber devices' expected longevity of devices' settings.

METHODS

Data from patients implanted with dual chamber devices (Symphony™, SORIN CRM SAS, Clamart, France) from 2003 to 2006 were collected in registries. Programmer files were retrieved: device-estimated longevity, assessed through algorithm prediction, was analyzed according to device settings.

RESULTS

One thousand sixty-eight recipients of dual chamber pacemaker in sinus rhythm (75.3±11.1 years, 54.5% male, ventricular block 30%, brady-tachy syndrome 21%, and sinus node dysfunction 49%) were followed up to 14.2±12.1 months (ranging from first quartile Q1: 2.9 months to fourth quartile Q4: 49.3 months) after implantation. DDD with automatic mode conversion and minimized ventricular pacing (SafeR) modes were programmed in 34.3%, 2.9%, and 62.8% of the patients, respectively. The mean total longevity estimated by the device was 134.1±31.5 months (11.2±2.6 years). Significant increase in longevity was observed in devices undergoing at least one reprogramming (134.4±31.4 months) versus device presenting no reprogramming (103.4±32.3 months, P=0.0005). The parameters associated with the major increase in mean longevity were the mode (mean longevity increase of +23.9 months in SafeR as compared to DDD mode, P<0.0001) and the atrial (A) and ventricular (V) amplitudes (mean longevity increase of +29.6 and +26.9 months for a decrease of less than 1V in A and V outputs respectively, P<0.0001).

CONCLUSION

This study provides information on dual chamber pacemakers' longevity and highlights the impact of devices' reprogramming on expected longevities.

Facilitation of the L-type calcium current in rabbit sino-atrial cells: effect on cardiac automaticity

OBJECTIVE

The L-type Ca(2+) current (I(Ca,L)) contributes to the generation and modulation of the pacemaker action potential (AP). We investigated facilitation of I(Ca,L) in sino-atrial cells.

METHODS

Facilitation was studied in regularly-beating cells isolated enzymatically from young albino rabbits (0.8-1 kg). We used the whole-cell patch-clamp technique to vary the frequency of the test depolarizations evoked at -10 mV or the conditioning diastolic membrane potential prior to the test pulse.

RESULTS

High frequencies (range 0.2-3.5 Hz) slowed the decay kinetics of I(Ca,L) evoked from a holding potential (HP) of -80 mV in 68% of cells resulting in a larger Ca(2+) influx during the test pulse. The amount of facilitation increased progressively between 0.2 and 3.0 Hz. When the frequency was changed from 0.1 to 1 Hz, the averaged increase in the time integral of I(Ca,L) was 27+/-7% (n=22). Application of conditioning voltages between -80 and -50 mV induced similar facilitation of I(Ca,L) in 73% of cells. The maximal increase of Ca(2+) entry occurred between -60 and -50 mV, and was on average 38+/-14% for conditioning prepulses of 5 s in duration (n=15). Numerical simulations of the pacemaker activity showed that facilitation of I(Ca,L) promotes stability of sino-atrial rate by enhancing Ca(2+) entry, thus establishing a negative feedback control against excessive heart rate slowing.

CONCLUSION

Facilitation of I(Ca,L) is present in rabbit sino-atrial cells. The underlying mechanism reflects modulation of I(Ca,L) decay kinetics by diastolic membrane potential and frequency of depolarization. This phenomenon may provide an important regulatory mechanism of sino-atrial automaticity.