A Novel Aortic Regurgitation Model from Cusp Prolapse with Hemodynamic Validation Using an Ex Vivo Left Heart Simulator.

Although ex vivo simulation is a valuable tool for surgical optimization, a disease model that mimics human aortic regurgitation (AR) from cusp prolapse is needed to accurately examine valve biomechanics. To simulate AR, four porcine aortic valves were explanted, and the commissure between the two largest leaflets was detached and re-implanted 5 mm lower to induce cusp prolapse. Four additional valves were tested in their native state as controls. All valves were tested in a heart simulator while hemodynamics, high-speed videography, and echocardiography data were collected. Our AR model successfully reproduced cusp prolapse with significant increase in regurgitant volume compared with that of the controls (23.2 ± 8.9 versus 2.8 ± 1.6 ml, p = 0.017). Hemodynamics data confirmed the simulation of physiologic disease conditions. Echocardiography and color flow mapping demonstrated the presence of mild to moderate eccentric regurgitation in our AR model. This novel AR model has enormous potential in the evaluation of valve biomechanics and surgical repair techniques. Graphical Abstract.

Hemodynamic Performance and Durability of Mosaic Bioprostheses for Aortic Valve Replacement, up to 13 Years.

BACKGROUND: This study evaluated the mid to long-term durability and hemodynamics of the small-size Mosaic bioprosthesis, a third-generation stented porcine bioprosthesis, for aortic valve replacement (AVR). METHODS AND RESULTS: From 2000 to 2012, 207 patients (117 women; age, 74±8 years; body surface area, 1.48±0.25 m(2)) underwent AVR with a Mosaic bioprosthesis. The mean follow-up period was 3.5±2.7 years (maximum, 12.4 years) and the follow-up rate was 93.7%. A 19-, 21-, 23-, 25-, and 27-mm prosthesis was used in 103, 53, 35, 13, and 3 patients, respectively. The measured effective orifice area was 1.17±0.25, 1.29±0.19, 1.39±0.24, and 1.69 cm(2)for the 19-25 mm prostheses, and the mean transvalvular pressure gradient was 19.4±6.0, 18.5±5.8, 16.5±7.3, and 13.2±2.9 mmHg, respectively. The left ventricular mass regression was significant (P<0.05) with rates of 74.6±18.8%, 75.5±30.2%, 68.1±30.5%, 55.9±12.9%, and 49.2%, respectively. The 30-day mortality rate was 1.9% and the 5- and 10-year actuarial survival rates were 86.0% and 73.7%, respectively. Valve-related comorbidities occurred in 3 patients (structural valve deterioration [SVD] in 1 after 7.2 years, and prosthetic valve endocarditis in 2). Freedom from SVD at 10-year was 96.7%. CONCLUSIONS: The mid to long-term performance of the small Mosaic bioprosthesis was satisfactory, with excellent hemodynamics and few valve-related adverse events.

Aortic valve repair via neo-chordae technique: mechanistic insight through numerical modelling.

Recently, the neo-chordae technique (NCT) was proposed to stabilize the surgical correction of isolated aortic valve (AV) prolapse. Neo-chordae are inserted into the corrected leaflet to drive its closure by minimal tensions and prevent relapses. In a previous in vitro study we analysed the NCT effects on healthy aortic roots (ARs). Here we extend that analysis via finite element models (FEMs). After successfully replicating the experimental conditions for validation purposes, we modified our AR FEM, obtaining a continent AV with minor isolated prolapse, thus representing a realistic clinical scenario. We then simulated the NCT, and systematically assessed the acute effects of changing neo-chordae length, opening angle, asymmetry and insertion on the aorta. In the baseline configuration the NCT restored physiological AV dynamics and coaptation, without inducing abnormal leaflet stresses. This outcome was notably sensitive only to neo-chordae length, suggesting that the NCT is a potentially easy-to-standardize technique. However, this parameter is crucial: major shortenings (6 mm) prevent coaptation and increase leaflet stresses by 359 kPa, beyond the yield limit. Minor shortenings (2-4 mm) only induce a negligible stress increase and mild leaflet tethering, which however may hamper the long-term surgical outcome.

Assessment and repair of aortic valve cusp prolapse: implications for valve-sparing procedures.

OBJECTIVES: Cusp prolapse causing aortic insufficiency is associated with unique echocardiographic, clinical, and surgical features. Recognition and appropriate surgical repair of this pathologic condition can not only treat affected patients but also improve results of aortic valve-sparing procedures, for which pre-existing or induced cusp prolapse is an important cause of failure. METHODS: Of 428 patients undergoing aortic valve repair, 195 (46%) were treated for cusp prolapse, and 111 (57%) of those had trileaflet aortic valve and make up this cohort. Cusp disease was the sole mechanism for aortic insufficiency (isolated group) in 50 patients whereas aortic dilatation was contributory in 61 (associated group). In total, 144 cusps were repaired in 111 patients. Preoperative echocardiograms, intraoperative findings, and clinical and echocardiographic outcomes were reviewed. RESULTS: On preoperative echocardiography, presence of an eccentric aortic insufficiency jet, regardless of severity, had 92% sensitivity and 96% specificity for the detection of single cusp prolapse. A transverse fibrous band was characteristically identified on the prolapsing cusp (sensitivity 57%; specificity 92%), correctly localizing a prolapsing cusp in all cases. Freedom from aortic valve reoperation at 8 years was 100% in the isolated group and 93% ± 5% in the associated group (p = 0.33). Freedom from recurrent aortic insufficiency (>2+) at 5 years was 90% ± 5% in the isolated and 85% ± 8% in the associated group (P = .54). The choice of surgical technique did not affect aortic insufficiency recurrence at follow-up (P = .6). CONCLUSIONS: Recognition and repair of isolated aortic cusp prolapse provides durable midterm outcome. An eccentric aortic insufficiency jet and a fibrous band can aid in the diagnosis and localization of cusp prolapse associated with ascending aortic disease and may help to improve results of aortic valve-sparing procedures.

Ventricular septal defect and aortic valve regurgitation: pathophysiology and indications for surgery.

As the velocity of a fluid increases a low-pressure zone is created, this is the Venturi effect and it explains the pathogenesis of aortic valve prolapse (AVP) and aortic insufficiency (AI) that is observed in a subset of patients with a ventricular septal defect (VSD). The VSDs complicated by AI are restrictive with high velocity shunting through the VSD, creating a low-pressure zone that impacts the adjacent aortic valve cusp resulting in AVP and subsequent AI. AVP and AI are therefore acquired lesions. AI is absent at birth because the forces necessary to create the low-pressure zone within the restrictive VSD do not exist in utero. The risk of development of AI increases during childhood, peaking at 5 to 10 years of age. VSD closure eliminates the low-pressure zone that is the cause of ongoing aortic valve cusp deformity and, if performed early, prevents development of AI. Patients with a subarterial VSD and AVP should undergo surgery to prevent the development of AI because this complicates about half of subarterial VSDs with AVP and spontaneous closure is rare. Patients with perimembranous VSDs with AVP should be followed with serial echocardiography and undergo VSD closure if more than trivial AI develops.

Hemodynamic performance following the Ross operation: comparison of two different techniques.

BACKGROUND AND AIM OF THE STUDY: The Ross operation as aortic valve replacement has undergone technical evolution. Originally described as a subcoronary implant, the full-root replacement technique is now more common worldwide. It remains unclear which of the two techniques has the better results. Hence, the hemodynamic performances of the two implantation methods, as applied by two experienced centers, were compared as part of the German Ross Registry. METHODS: In total, 132 (Group 1, root replacement, mean age 40 +/- 14 years) and 249 (Group 2, subcoronary implant, mean age 48 +/- 14 years) consecutively operated patients were compared clinically and echocardiographically. Data were analyzed focusing on pulmonary autograft and homograft function at mid-term (2.78 +/- 1.89 versus 2.26 +/- 2.11 years). RESULTS: Echocardiography revealed autograft peak systolic gradients of 5.0 +/- 2.7 mmHg for Group 1 and 6.7 +/- 3.7 mmHg for Group 2 (p < 0.05), and an indexed effective orifice area (EOA) of 1.98 +/- 0.57 cm2/m2 and 1.64 +/- 0.43 cm2/m2 (p < 0.05), respectively. Homograft peak systolic gradients were 15.6 +/- 9.0 mmHg and 11.7 +/- 6.8 mmHg for Groups 1 and 2 (p < 0.05) respectively, and the indexed EOA with regard to the homograft was 1.08 +/- 0.49 cm2/m2 and 1.26 +/- 0.50 cm2/m2 (p < 0.05). Autograft insufficiency grade > I was present in 1.5% (2/132) of Group 1 and 2.8% (7/249) of Group 2 patients. Pulmonary insufficiency grade > I was 17.4% (23/132) for Group 1 and 4.8% (12/249) for Group 2 (p < 0.05). CONCLUSION: Although both groups enjoyed excellent hemodynamics in the mid-term, the root replacement technique had the advantage of larger annulus diameters and greater aortic EOA. Clinically relevant autograft regurgitation in both groups was gratifyingly rare, and seemed to be independent of surgical technique. Long-term durability of the more demanding subcoronary technique versus the problems of larger dimensions of the sinus of Valsalva and sinotubular junction in the free-root technique, remains to be proven. Apparent differences in pulmonary homograft hemodynamics can most likely be explained by surgical differences, younger patients in Group 1, and by homograft variation.

Morphological analysis of aortic root in eccentric aortic regurgitation using anyplane two-dimensional images produced by transesophageal three-dimensional echocardiography.

BACKGROUND AND AIM OF THE STUDY: Evaluation of leaflet dysfunction in aortic valve repair is important. In eccentric aortic regurgitation (AR), it is unclear whether leaflet dysfunction other than prolapse exists. The study aim was to validate the hypothesis that eccentric AR correlates with leaflet dysfunction. METHODS: Both anyplane 2-D images produced by a 3-D reconstruction system and surgical views for 21 patients with eccentric AR (11 with aortic valve prolapse, group A; 10 without prolapse, group B) were analyzed prospectively. Vertical height from annulus to coaptation point (termed AC), and distance from coaptation point to sinotubular junction (CS) were measured at early diastole. RESULTS: For group A, AC and CS values were 1.3 +/- 2.2 mm and 25.9 +/- 3.4 mm respectively for leaflets of eccentric AR jet origin, and 3.8 +/- 0.4 mm and 22.7 +/- 2.1 mm for other leaflets. For group B, AC and CS values were 4.7 +/- 0.9 mm and 39.8 +/- 7.0 mm for leaflets of eccentric AR jet origin, and 7.8 +/- 0.9 mm and 31.9 +/- 5.7 mm for other leaflets. The AC for leaflets of eccentric AR jet origin was smaller than AC for other leaflets (p < 0.01) between both groups. There was no difference between CS for leaflets of eccentric AR jet origin and other leaflets in group A, but CS for leaflets of eccentric AR jet origin was larger than for other leaflets in group B (p <0.01). AC and CS values for leaflets of eccentric AR jet origin in group B were larger than those for group A. Leaflets of eccentric AR jet origin were always shifted toward the direction of the base in the anyplane images, and elongated in the surgical view. CONCLUSION: Anyplane 2-D images obtained by 3-D echocardiography showed that aortic leaflets of eccentric AR jet origin shifted towards the direction of the base with or without prolapse, and were accompanied by dysfunction. Color flow Doppler determination of the eccentricity of AR jet origin was useful in predicting aortic valve dysfunction.

Dicrotic pulse observed in a patient with prolapse of the aortic valve without aortic regurgitation.

We describe a case of dicrotic pulse in a patient who exhibited marked prolapsed aortic cusp without aortic regurgitation. Echo-Doppler in the abdominal aorta showed deep reversal flow confined to early diastole. We conclude that this prolapse was the cause of the steep dicrotic notch and the dicrotic pulse, because of the concomitance of non-leaking aortic valves.

[Valvular prolapse (clinical, echocardiographic, phonocardiographic and electrocardiographic features)]. / Prolapsy klapanov (klinicheskaia, ékhokardiograficheskaia, fonokardiograficheskaia i élektrokardiograficheskaia kharakteristiki).

Clinical, echoCG, PCG and ECG examinations were performed in 42 patients with primary isolated valve prolapses: mitral, aortal and tricuspid (32, 5 and 5 patients, respectively). It is shown that degree 1 regurgitation caused no hemodynamic disturbances, that of degree 2 and 3 brought about cardial complaints in more than half the patients, hemodynamic overstrain of the heart, sound symptoms similar to those of relevant valvular disease.

Floppy mitral valves in elderly patients: clinical features and associated echocardiographic findings.

The clinical features and echocardiographic findings of a series of elderly patients with floppy mitral valves are presented. Palpitation was a common presenting complaint and 50% of patients had significant arrhythmias documented. Chest-wall deformity or Marfanoid habitus were common clinical findings. Seventy-nine per cent of patients had associated myxomatous degeneration of the aortic valve. The high incidence of arrhythmias in the series gives cause for concern since all required anti-arrhythmic therapy. The identification of these patients is therefore of practical importance.

[Collapse of the aortic valve in dilated myocardiopathies: echocardiographic study]. / O colapso da válvula aórtica nas miocardiopatias dilatadas: estudo ecocardiográfico.

In order to clarify the early systolic partial closure (notching) of aortic valve in patients (pts) with dilated cardiomyopathy (DC), authors (AA) evaluated the M-mode echocardiograms corresponding to 41 pts with DC. Pts were separated in two groups, according to the presence of systolic notching: group A (18 pts) presenting systolic notching; group B (23 pts) in which no systolic notching was observed. For each group, the same echocardiographic parameters were evaluated related to aortic root, left atrium, left ventricule (LV), aortic valve and mitral valve. Both groups were compared statistically. Results--Group A presented a reduced motion of aortic root and greater initial maximal aortic cuspids separation. AA therefore conclude that in pts with DC the systolic notching has no eventual relation with mitral regurgitation. In this setting no conclusions about LV function can be inferred, and it is suggested that systolic notching may bear some relation with differences in the distribution of transvalvular aortic flow.