P4724Elevated mitral valve pressure gradient is predictive for long-term outcome after percutaneous edge-to-edge mitral valve repair (PMVR) in patients with degenerative MR, but not in functional MR

Background

To analyze the effects of residual mitral regurgitation (MR) and mean mitral valve pressure gradient (MVPG) after percutaneous edge-to-edge mitral valve repair (PMVR) using the MitraClip-system on long term outcome.

Methods and results

Two hundred fifty-five patients who underwent PMVR were analyzed. Kaplan-Meier and Cox regression analyses were performed to evaluate the impact of residual MR and MVPG on clinical outcome. A combined clinical endpoint (all-cause mortality, MV surgery, redo procedure, implantation of a left ventricular assist device) was used.

After PMVR, mean MVPG increased from 1.6±1.0 mmHg to 3.1±1.5 mmHg (p<0.001). Reduction of MR severity to ≤2+ postintervention was achieved in 98.4% of all patients. In the overall patient cohort, residual MR was predictive for the combined endpoint while elevated MVPG >4.4 mmHg was not according to Kaplan-Meier and Cox regression analyses. We then analyzed the cohort with degenerative and that with functional MR separately to account for these different entities.In the cohort with degenerative MR, elevated MVPG was associated with increased occurrence of the primary endpoint, whereas this was not observed in the cohort with functional MR.

Conclusions

MVPG >4.4 mmHg after MitraClip-implantation was predictive for clinical outcome in the patient cohort with degenerative MR. In the patient cohort with functional MR, MVPG >4.4 mmHg was not associated with increased clinical events.

Acknowledgement/Funding

This study was supported by grants from the German Research Foundation (KFO 274), the Volkswagen Foundation (Lichtenberg Program) and the German Heart

Acquired von Willebrand syndrome in congenital heart disease surgery: results from an observational case-series

Essentials Bleeding complications during congenital heart disease surgery in neonatal age are very common. We report the perioperative incidence of acquired von Willebrand syndrome (aVWS) in 12 infants. aVWS was detected in 8 out of 12 neonates and infants intraoperatively after cardiopulmonary bypass. Ten patients received von Willebrand factor concentrate intraoperatively and tolerated it well. SUMMARY: Background Cardiac surgery of the newborn and infant with complex congenital heart disease (CHD) is associated with a high rate of intraoperative bleeding complications. CHD-related anatomic features such as valve stenoses or patent arterial ducts can lead to enhanced shear stress in the blood stream and thus cause acquired von Willebrand syndrome (aVWS). Objective To evaluate the intraoperative incidence and impact of aVWS after cardiopulmonary bypass (CPB) in neonates and infants with complex CHD. Patients/Methods We conducted a survey of patients aged < 12 months undergoing complex cardiac surgery in our tertiary referral center. Twelve patients, whose blood samples were analyzed for aVWS before CPB and immediately after discontinuation of CPB on a routine basis, were eligible for the analysis. von Willebrand factor antigen (VWF:Ag), ristocetin cofactor activity (VWF:RCo), collagen binding activity (VWF:CB), VWF:multimers and factor VIII activity (FVIII:C) were determined. Results aVWS was diagnosed by VWF multimer analysis in 10 out of 12 patients (83%) prior to surgery and intraoperatively at the end of CPB in 8 out of 12 patients (66%). Ten patients received VWF/FVIII concentrate intraoperatively as individual treatment attempts during uncontrolled bleeding. They tolerated it well without intraoperative thrombotic events. One patient suffered a transient postoperative cerebral sinuous vein thrombosis. Conclusions aVWS is of underestimated incidence in complex CHD surgery. These data may offer a new approach to reduce the risk of severe bleedings and to achieve hemostasis during high-risk pediatric cardiac surgery by tailoring the substitution with von Willebrand factor concentrate.

Development, preclinical evaluation and validation of a novel quick vascular closure device for transluminal, cardiac and radiological arterial catheterization

Following percutaneous coronary intervention, vascular closure devices (VCDs) are increasingly used to reduce time to ambulation, enhance patient comfort, and reduce potential complications compared with traditional manual compression. Newer techniques include complicated, more or less automated suture devices, local application of pads or the use of metal clips and staples. These techniques often have the disadvantage of being time consuming, expensive or not efficient enough. The VCD failure rate in association with vascular complications of 2.0-9.5%, depending on the type of VCD, is still not acceptable. Therefore, the aim of this study is to develop a self-expanding quick vascular closure device (QVCD) made from a bioabsorbable elastic polymer that can be easily applied through the placed introducer sheath. Bioabsorbable block-co-polymers were synthesized and the chemical and mechanical degradation were determined by in vitro tests. The best fitting polymer was selected for further investigation and for microinjection moulding. After comprehensive haemocompatibility analyses in vitro, QVCDs were implanted in arterial vessels following arteriotomy for different time points in sheep to investigate the healing process. The in vivo tests proved that the new QVCD can be safely placed in the arteriotomy hole through the existing sheath instantly sealing the vessel. The degradation time of 14 days found in vitro was sufficient for vessel healing. After 4 weeks, the remaining QVCD material was covered by neointima. Overall, our experiments showed the safety and feasibility of applying this novel QVCD through an existing arterial sheath and hence encourage future work with larger calibers.

Aortic Elongation and Stanford B Dissection: The Tübingen Aortic Pathoanatomy (TAIPAN) Project

OBJECTIVE/BACKGROUND

Aortic elongation has not yet been considered as a potential risk factor for Stanford type B dissection (TBD). The role of both aortic elongation and dilatation in patients with TBD was evaluated.

METHODS

The aortic morphology of a healthy control group (n = 236) and patients with TBD (n = 96) was retrospectively examined using three dimensional computed tomography imaging. Curved multiplanar reformats were used to examine aortic diameters at defined landmarks and aortic segment lengths.

RESULTS

Diameters at all landmarks were significantly larger in the TBD group. The greatest diameter difference (56%) was measured in dissected descending aortas (p < .001). The segment with the most considerable difference between the study groups with regard to elongation was the non-dissected aortic arch of patients with TBD (36%; p < .001). Elongation in the aortic arch was accompanied by a diameter increase of 21% (p < .001). In receiver-operating curve analysis, the area under the curve was .85 for the diameter and .86 for the length of the aortic arch.

CONCLUSIONS

In addition to dilatation, aortic arch elongation is associated with the development of TBD. The diameter and length of the non-dissected aortic arch may be predictive for TBD and may possibly be used for risk assessment in the future. This study provides the basis for further prospective evaluation of these parameters.

Pitfalls in Echocardiography: Coarctation of the Aorta Presenting as Dilated Cardiomyopathy (DCM)

Purpose: The morphologic spectrum of aortic coarctation extends from discrete isthmic obstruction to tubular hypoplasia of the entire aortic arch. Neonates with coarctation frequently present with congestive heart failure and critically reduced perfusion of the descending aorta following ductal closure. During the recent years we observed several infants with coarctation who presented beyond the neonatal period with dilated cardiomyopathy (DCM). We reviewed our patients with coarctation to determine whether this presentation represents an exception or is relevant for the differential diagnosis of children with DCM. Materials and Methods: From 1/2001 to 12/2013 74 babies with isolated coarctation were diagnosed in our institution. 50 patients presented in the neonatal period and 24 patients beyond the first month. Results: 5/74 infants presented after the neonatal period with poorly contractile, dilated left ventricles. Echocardiographic detection of the coarctation was facilitated by application of the ductal view and by Doppler interrogation of the celiac artery revealing a significantly diminished systolic flow velocity. All patients underwent resection of the coarctation and end-to-end anastomosis of the aorta. Postoperative normalization of left ventricular function was observed within a median interval of 2 months. Conclusion: Coarctation of the aorta presenting as DCM accounted for 21 % of our infants with coarctation who presented beyond the neonatal period and 7 % of those in the first year of life. The stenosis was difficult to detect because of its distal location and normal configuration of the aortic arch. Isthmic coarctation should be included in the differential diagnosis of infants with DCM and requires careful examination of the isthmic region in these children.