Creation of Ventricular Septal Defects on the Beating Heart in a New Pig Model

Abstract

Background/Aims: So far, surgical and interventional therapies for muscular ventricular septal defects (mVSDs) beyond the moderator band have had their limitations. Thus, alternative therapeutic strategies should be developed. We present a new animal model for the evaluation of such strategies. Methods: In a pig model (n = 9), anterolateral thoracotomy was performed for exposure of the left ventricle. mVSDs were created under two- and three-dimensional echocardiography with a 7.5-mm sharp punch instrument, which was forwarded via a left ventricular puncture without extracorporeal circulation. Results: Creation of mVSDs was successful in all animals (n = 9) confirmed by echocardiography, hemodynamic measurements and autopsy. The defects were located in the midmuscular (n = 4), apical (n = 1), inlet (n = 2) and anterior part (n = 2) of the muscular septum. All animals were hemodynamically stable for further procedures. The diameter and shunt volume of the mVSDs were 4.8–7.3 mm (mean: 5.9 mm) and 12.9–41.3% (mean: 22.1%), respectively. Autopsy confirmed in all animals the creation of a substantial defect. Conclusion: The described new technique for creation of an mVSD on the beating heart in a pig model is suitable for the evaluation of new therapeutic strategies for mVSD closure.

Evaluation of a new hybrid technique for closure of muscular ventricular septal defects in a long-term setting

“…In short-term porcine model, we demonstrated the general feasibility of this technique. 16 In this study, we report our results on the evaluation of this technique in a long-term porcine model in which residual shunting, development of LV dysfunction, and integration of the patch into the septum were especially addressed.…”

“…Anesthesia and surgical preparation were performed as described previously. 14,16 Briefly, the right-sided carotid artery and jugular vein were surgically exposed, and the artery was cannulated with a 9F introducer sheath and the vein with an 11F introducer sheath. Arterial pressure and central venous pressure were measured continuously.…”

“…Creation of mVSDs was achieved under 2-and 3-dimensional echocardiographic guidance, as described previously. 16 For 2-dimensional echocardiography (Sonos 5500; Philips Healthcare Nederland BV, Eindhoven, The Netherlands), a 5-MHz transesophageal echocardiographic probe was placed behind the heart through an additional incision in the sixth intercostal space. Epicardial real-time 3-dimensional echocardiography was performed with the X7-2 matrix transducer of the iE33 Ultrasound System (Philips Healthcare).…”

Preclinical evaluation of a new self‐expanding device for closure of muscular ventricular septal defects in a pig model

“…Anesthesia and surgical preparation was performed as described before [22]. Shortly, the animals were put on the ventilator and anesthetized with propofol (induction 1.5–2 mg/kg BW), maintenance 10 mg/kg BW/h; Fresenius Kabi, Bad Homburg, Germany), and fentanyl (induction 0.02 mg/kg BW, maintenance 0.045 mg/kg BW/h, DeltaSelect, Dreieich, Germany).…”

“…Creation of mVSDs was carried out under two‐dimensional (2D) guidance as described previously [22]. For 2D echocardiography (Sonos 5500, Philips Healthcare, Eindhoven, Netherlands), a 5 MHz transesophageal echocardiographic probe was placed behind the heart via an additional incision.…”