Raffaele Scaffa

Opening and closing characteristics of the aortic valve after valve-sparing procedures using a new aortic root conduit

BACKGROUND The durability of aortic valve-sparing procedures is negatively affected by increased leaflet stress in the absence of normally shaped sinuses of Valsalva. We compared valve motion after remodeling procedures using a standard conduit and a specifically designed aortic root conduit. METHODS Echocardiographic studies of the aortic valve dynamics were performed in 14 patients after remodeling of the aortic root (7 standard conduits, group A; 7 new conduits, group B) and in 7 controls (group C). Opening and closing leaflet velocities and percent of slow closing leaflet displacement were measured. Root distensibility and the pressure strain of the elastic modulus were measured at all root levels. RESULTS Root distensibility and the pressure strain of the elastic modulus were different in group A and B only at the sinuses (p < 0.001). Opening and closing leaflet velocities were not different among groups. Slow closing leaflet displacement was markedly more evident in group B patients (24.2%+/-1.9% versus 2.5%+/-1.9% in group A, p < 0.001) and similar to controls (22.1%+/-7.9%). CONCLUSIONS The new conduit guarantees dynamic features of the aortic valve leaflets superior to those obtained with standard conduits and more similar to normal subjects.

Analysis of valve motion after the reimplantation type of valve-sparing procedure (David I) with a new aortic root conduit.

BACKGROUND The reimplantation type of valve-sparing procedure does not allow proper reconstruction of the sinuses of Valsalva. We assessed the valve motion after a reimplantation type (David I) of valve-sparing procedure using a new Dacron conduit that incorporates sinuses of Valsalva. METHODS Nine consecutive patients undergoing an aortic valve-sparing procedure using the new conduit were studied using two-dimensional transesophageal echocardiography shortly (2 +/- 1 months) after operation to determine root distensibility, expressed as percent change in radius and as pressure strain of the elastic modulus. Next, monodimensional view was used to assess valve motion in its various phases (rapid valve opening velocity, slow closing leaflet displacement, rapid valve closing velocity, maximal leaflet displacement, and leaflet displacement before valve closure). Seven healthy individuals served as control subjects. RESULTS Root distensibility was reduced at the level of the annulus and sinotubular junction but was similar to control subjects at the level of the sinuses (percent change in radius, 4.1% +/- 0.8% versus 4.5% +/- 1.2%; pressure strain of the elastic modulus, 1,286 +/- 674 g/cm2 versus 1,195 +/- 628 g/cm2). Rapid valve opening (69 +/- 34.4 cm/s versus 51 +/- 11.9 cm/s) and closing (47.6 +/- 16 cm/s versus 36.4 +/- 9 cm/s) velocity as well as slow closing leaflet displacement (24% +/- 4.7% versus 22.1% +/- 7.9%), maximal leaflet displacement (20.1 +/- 4 mm versus 22.7 +/- 1.9 mm), and leaflet displacement before valve closure (15.2 +/- 3 mm versus 17.6 +/- 0.8 mm) were similar to control subjects. CONCLUSIONS The new aortic root conduit used in a reimplantation type of valve-sparing procedure allows the anatomic reconstruction of the aortic root with leaflet motion similar to that of normal subjects.

Use of the Valsalva graft and long-term follow-up.

OBJECTIVE The Valsalva graft is a specifically designed Dacron graft that, on implantation and pressurization, generates pseudosinuses of Valsalva. We reviewed a multicenter experience of the reimplantation procedure with the Valsalva graft in patients with aneurysms involving the aortic root. METHODS A total of 278 patients underwent valve-sparing aortic root replacement using the Valsalva graft at 4 different Italian cardiac surgery centers and were studied by clinical assessment and echocardiography. Of the 278 patients, 220 were men (79%), with a mean age of 56 ± 15 years. Of the patients, 42 (15%) had Marfan syndrome, 31 (11%) had a bicuspid aortic valve, 13 (5%) had acute aortic dissection, and 136 (49%) had grade 3 or 4+ aortic insufficiency. Concomitant cardiac procedures were performed in 78 patients (28%). Additional aortic leaflet repair was necessary in 25 patients (9%). The mean crossclamp time was 120 ± 27 minutes. RESULTS There were 5 (1.8%) operative and 5 (1.8%) late deaths. The mean follow-up was 52 ± 28 months (range, 2-112 months) and was 100% complete. The cumulative actuarial survival was 95.2% (268 patients). A total of 32 patients (11%) had grade 3 to 4+ aortic insufficiency, and 17 of these required late aortic valve replacement (range, 3-78 months). At 10 years of follow-up, the freedom from aortic valve reoperation rate was 91%, and the rate of freedom from residual aortic insufficiency not needing reoperation was 88%. CONCLUSIONS The reimplantation type of valve-sparing procedure can be facilitated by the use of the Valsalva graft and can be performed with satisfactory perioperative and midterm results. How an optimal root reconstruction will affect the second decade of follow-up has yet to be determined.

Long-term results of the valve reimplantation technique using a graft with sinuses

OBJECTIVE Aortic valve reimplantation is the most commonly used technique to spare the aortic valve. Long-term results data are scarce and available only with the use of standard straight graft. We examined the long-term results of reimplantation of the aortic valve using a graft incorporating sinuses of Valsalva. METHODS From May 2000 to December 2014, 124 patients had an aortic valve reimplanted into a graft with sinuses of Valsalva. The mean age was 53 ± 13 years and the majority were men (87%). Marfan syndrome was present in 21 patients (17%) and 12% had a bicuspid valve. Patients were prospectively followed by means of transthoracic echocardiography. The mean follow-up was 63 ± 52 months. RESULTS Overall survival at 5, 10, and 13 years was 94.4% ± 2.2%, 90.5% ± 4.4%, and 81.4% ± 7.3%, respectively. Six patients required reoperation within a time frame of 6 to 96 months. None of the patients died at reoperation. Freedom from reoperation was 95.4% ± 2.3% at 5 years and 90.1% ± 4.3% at 10 and 13 years. All patients who needed reoperation had surgery during the first 5 years. Three patients had residual aortic insufficiency >2. Considering also all patients who underwent reoperation because of aortic insufficiency, freedom from moderate to severe residual aortic insufficiency was 94.1% ± 2.6% at 5 years, and 87.1% ± 4.7% at 10 and 13 years. CONCLUSIONS The majority of patients who had their valve reimplanted in a graft with sinuses continue to perform well after 10 years.

Role of the sinuses of Valsalva on the opening of the aortic valve

OBJECTIVE The present in vitro study was designed to ascertain whether the presence of sinuses of Valsalva in the aortic root were able to regulate the valve effective orifice area and modulate the gradient across the valve independently from root compliance. METHODS Four different root configurations were prepared. Of the 4, 2 were silicon configurations with the same compliance, 1 with and 1 without sinuses of Valsalva, in which a 25-mm Solo stentless aortic valve was sutured inside. The other 2 configurations were obtained by substituting the upper part of the root with a straight Dacron graft or with a Valsalva graft in a remodeling fashion to reproduce the surgical situation. All roots were mounted in a pulse duplicator to measure the pressure decrease across the valve and effective orifice area at different cardiac outputs. RESULTS With increasing cardiac output up to 7 L/min, an increase in the pressure decrease across the valve was evident in both configurations without sinuses of Valsalva (7.90 ± 1.7 and 11 mm Hg ± 0.1 mm Hg, respectively) but not in those with sinuses (2.87 ± 0.5 and 2.42 mm Hg ± 0.5 mm Hg). Similarly, with increasing cardiac output, the effective orifice area increased significantly only in the roots with sinuses (5.13 ± 0.5 and 5.47 ± 0.5 vs 3.06 ± 0.3 and 2.50 cm(2) ± 0.02 cm(2), respectively). CONCLUSIONS When the cardiac output is increased to greater than the resting physiologic values, the presence of sinuses of Valsalva, independently of root compliance, prevents an increase in the pressure decrease across the valve by way of an increase of the effective orifice area.

The combined role of sinuses of Valsalva and flow pulsatility improves energy loss of the aortic valve

OBJECTIVES Normal aortic valve opening and closing movement is a complex mechanism mainly regulated by the blood flow characteristics and the cyclic modifications of the aortic root. Our previous in vitro observations demonstrated that the presence of the Valsalva sinuses, independently from root compliance, is important in reducing systolic pressure drop across the aortic valve. This in vitro study was designed to ascertain if this effect is dependent on the flow characteristics. METHODS Stentless 21, 23 and 25 mm aortic prostheses were sutured inside Dacron graft with and without sinuses. Hydrodynamic performance of the root models was investigated in steady-state (continuous) and unsteady-state (pulsatile) flow regimes. Aortic transvalvular pressure drop and effective orifice area (EOA) were evaluated. RESULTS The continuous flow analysis revealed that no marked differences in pressure drop characterized the two root configurations at flow regimes lower than 15 l/min, independently of valve size. Conversely, at higher flow regimes (up to 30 l/min) a relatively low pressure drop continued to characterize grafts with sinuses, whereas marked increments in pressure drop were measured in straight grafts, especially in the smaller size (77.05 ± 4.58 vs 23.80 ± 2.44 mmHg; 18.40 ± 1.31 vs 7.66 ± 0.37 mmHg and 29.54 ± 0.17 vs 7.12 ± 0.07 mmHg, for 21, 23 and 25 mm valve, respectively). Under pulsatile conditions, the presence of sinuses clearly confirmed lower pressure drops also more evident in the smaller valve sizes (53.89 ± 1.06 vs 11.6 ± 0.24 mmHg at 7 l/min for 21 mm valve). EOA values were always lower in the absence of sinuses. In continuous flow regimes, at 30 l/min EOA of 25 mm valve size was 3.67 ± 0.02 cm(2) in the Valsalva model versus 1.79 ± 0.01 cm(2) for the Straight model. In pulsatile tests, at 7 l/min a 25-valve size demonstrated an EOA of 5.47 ± 0.60 in the Valsalva model versus 2.50 ± 0.02 cm(2) in the Straight model. CONCLUSIONS These findings (i) confirm the hypothesis that the sinuses of Valsalva play a key role in optimizing the aortic haemodynamics during systole, minimizing energy losses; (ii) suggest that the sinuses of Valsalva are needed because of the complex nature of blood flow during ejection.

Differences in aortic cusp coaptation between the reimplantation and the remodeling techniques of aortic valve–sparing surgery: An in vitro porcine model study

OBJECTIVES We sought to evaluate the effects of the reimplantation type versus the remodeling type of aortic valve-sparing technique on the geometry of the same aortic root. METHODS Fifteen fresh isolated porcine hearts with normal aortic valves and a standard aortoventricular junction size of 23 mm were processed. An aortic valve-sparing replacement was performed by reimplanting the native aortic root inside a 28-mm Valsalva graft (Vascutek Ltd, Renfrewshire, UK). Hearts were subsequently implanted with instruments in a test circuit, and the aortic roots were pressurized at a fixed pressure of 100 mm Hg. Diameters of the aortoventricular junction, of the sinuses, and of the sinotubular junction, as well as effective height and coaptation height of aortic valve leaflets, were measured by echography. Transition from the reimplantation to the remodeling configuration was then achieved by longitudinally cutting the skirt of the graft from the annulus to the top of each commissure. The same measurements were then repeated. RESULTS After transition from the reimplantation to the remodeling configuration, significant increases in the sizes of the aortoventricular junction and of the sinuses were observed. Effective height and coaptation height significantly decreased, and the rounded cross-sectional profile of the aortic valve leaflets flattened. CONCLUSIONS In the same aortic root, transition from the reimplantation to the remodeling configuration of aortic valve-sparing surgery results in a significant increase in aortic root sizes and in a significant reduction of effective height and coaptation height, suggesting a less satisfactory result.

Intraaortic Migration of an Epicardial Pacing Wire: Percutaneous Extraction

Infrequent but serious complications have been described in association with temporary epicardial pacing wires. We describe the case of an intraaortic migration of an infected retained atrial temporary epicardial pacing wire and the transfemoral percutaneous interventional approach for its extraction.

The Valsalva graft in aortic valve repair and replacement.

Presentation of the use of the new Valsalva graft that incorporates sinuses of Valsalva: its use is mostly recommended for the reimplantation type of valve sparing procedure where it combines the advantages of proper anatomical reconstruction with those of annular stabilization. Its advantages when used in the remodeling technique or in a classical Bentall procedure are also shown. The problem of graft sizing and of proper geometrical reconstruction of the aortic root are addressed.

Voluminous Atrial Septal Aneurysm May Mask a Large Double Atrial Septal Defect

P l d g s r fi 1 A42-year-old man presented with a history of a transient ischemic attack and diagnosis of atrial septal aneurysm (ASA) type 3RL according to Olivares-Reyes criteria [1]. The previous workup failed to show any interatrial shunt. An electrocardiogram-gated computerized tomography scan revealed an atrial septal aneurysm involving most of the interatrial septum and protruding into the right atrium without a clear evidence of interatrial communication (Fig 1, arrow; LA left atrium; LV left ventricle; RA right atrium; RV right venricle). The transcranial Doppler showed high-intensity ignals under the Valsalva maneuver and raised the oubt of a patent foramen ovale. Surgery was scheduled ecause of the transient ischemic attack and the suspiious of communication between the atrial chambers.