Guido Gelpi

Targeting Landing Zone 0 by Total Arch Rerouting and TEVAR: Midterm Results of a Transcontinental Registry

BACKGROUND Landing zone 0, defined as a proximal landing zone in the ascending aorta, remains the last frontier to be taken. Midterm results of total arch rerouting and thoracic endovascular aortic repair (TEVAR) extending into landing zone 0 remain to be determined. METHODS From 2003 to 2011, 66 patients (mean age, 70 years; 68% men) presenting with pathologic conditions affecting the aortic arch (atherosclerotic aneurysms [n = 48], penetrating ulcers [n = 6], type B dissections [n = 6], type B after type A dissections [n = 5], and anastomotic aneurysm [n = 1]) were treated in 5 participating centers. Of these 66 patients, only 12% would have been deemed suitable for any kind of conventional surgical repair because of multisegmental aortic disease or comorbidities. RESULTS In-hospital mortality was 9%. Retrograde type A dissection was observed in 3% of patients. The assisted type I and type III endoleak rate was 0%. Stroke was seen in 5% of patients. Permanent paraplegia was observed in 3% of those studied. Median follow-up was 25 months (8-41 months). There was 1 late type Ib endoleak, which was followed by watchful waiting. Five-year survival was 72%. Five-year aorta-related survival was 96%. No aorta-related reintervention had to be performed in the segments treated. CONCLUSIONS Midterm results of total arch rerouting and TEVAR extending into landing zone 0 are excellent in regard to aorta-related survival and freedom from aorta-related reintervention. Retrograde type A dissection, potentially related to compliance mismatch between the ascending aorta and the stent-graft, warrants further attention. Extended application of this strategy augments therapeutic options in a group of patients who are not suitable candidates for conventional therapy.

Assessment of an aortosaphenous vein graft anastomotic device in coronary surgery: Clinical experience and early angiographic results

BACKGROUND Until now technologic evolution in coronary bypass surgery has focused on extracorporeal circulation, on operation without extracorporeal circulation, and on the exposure of the operative site. Recently a one-shot anastomotic device for the proximal anastomosis in coronary surgery was developed. We investigated whether the use of the aortic connector system (ACS) could facilitate the creation of aortosaphenous vein graft anastomoses in myocardial revascularization. METHODS From November 2000, 40 ACS devices were used in 36 consecutive patients (mean age 70.7 +/- 8.9 years); 12 patients (33.3%) underwent surgery on pump and 24 patients (66.6%) off pump; 50 distal anastomoses were performed. In all cases the connection with the ascending aorta was created before the distal anastomoses because of the necessity to slide the saphenous vein graft (SVG) over the vein transfer sheath. Intraoperative graft function was tested measuring blood flow by Doppler analysis. Postoperative evaluation of the anastomotic patency was carried out by early angiography in 34 patients (94.7%) but was excluded in 5 patients (5.3%) with extensive extracardiac vascular occlusive disease. RESULTS Of 38 AC (95%) evaluated, 36 (94.7%) functioned properly. The end-to-side proximal anastomosis without aortic clamping is instantaneous, the quality of anastomoses was highly rated, no additional stitches were required, and all coronary arteries could be reached. Intraoperative quantity flow was measured by Doppler analysis and all but one showed good flow. Early postoperative angiography demonstrated good patency of the grafts in all cases but 2 (5.3%). At 1-year follow-up, 1 patient died of stroke; all other patients remained free of symptoms and no reoperation was required. CONCLUSIONS The use of ACS makes end-to-side anastomosis rapid, effective, and reproducible while eliminating aortic cross clamping; it opens a new era in beating or nonbeating coronary surgery. Long-term results are mandatory to confirm our favorable preliminary results.

Myocardial revascularization with multiple arterial grafts: comparison between the radial artery and the right internal thoracic artery

BACKGROUND Bilateral internal thoracic artery (ITA) harvesting is significantly underused, whereas the radial artery is being used with increasing frequency. We have retrospectively analyzed perioperative and short-term outcomes of patients receiving a radial artery versus those receiving a right ITA as a second arterial graft. METHODS Between February 1999 and May 2000, 250 patients underwent coronary artery bypass grafting using the radial artery (156 patients) or the right ITA (94 patients) in combination with the left ITA and, when required, the saphenous vein. RESULTS There was a higher prevalence of risk factors in the radial artery group. More coronary artery bypass graftings (p < 0.001) were performed with the radial artery. Operative mortality was not different (p = not significant). In the right ITA group there was more bleeding (p < 0.001) and a longer hospital stay (p < 0.001). Mean follow-up was 8.1 +/- 3.9 months. The probability of survival was similar (p = not significant). CONCLUSIONS The radial artery can extend the benefits of multiple arterial grafting to those patients who are usually excluded from bilateral ITA harvesting because of multiple risk factors. Perioperative and short-term results are good.

Predictors and outcomes of acute kidney injury after thoracic aortic endograft repair

BACKGROUND This study analyzed the incidence and the predictive factors of postoperative acute kidney injury (AKI) after thoracic endovascular aortic repair (TEVAR) and evaluated the effect of AKI on postoperative survival. METHODS Between November 2000 and April 2011, all consecutive patients undergoing TEVAR of the descending thoracic or thoracoabdominal aorta were enrolled at four teaching hospitals. Estimated glomerular filtration rate (eGFR) was evaluated during the entire hospitalization. AKI was defined by the RIFLE (Risk, Injury, Failure, Loss of function, End-stage renal disease) consensus criteria. RESULTS The study included 171 patients (80% men) who were a mean age of 69±14 years (range, 18-87 years). AKI occurred in 24 patients (14%). Independent predictors of postoperative AKI were preoperative depressed eGFR, thoracoabdominal extent, and postoperative transfusion. Patients with AKI experienced major postoperative complications (P=.001), longer hospitalization (P=.008), and higher hospital mortality (29% vs 4%; P<.001). Kaplan-Meier analysis showed a survival of 82%, 51%, and 51% at 1, 3, and 5 years for patients who developed AKI, which was significantly worse than the 99%, 89%, and 80% for patients who did not experience AKI (P=.001). CONCLUSIONS Preoperative poor renal function, blood transfusions, and the thoracoabdominal extent of the aortic disease were the most important predictors for AKI.

Effects of heart rate on phasic Y-graft blood flow and flow reserve in patients with complete arterial myocardial revascularizaton: an intravascular Doppler catheter study

OBJECTIVE It is not well established whether the blood flow of arterial composite Y-grafts can efficiently respond to the flow demand of the coronary system early postoperatively. The aim of this study was to evaluate if soon after the operation, arterial composite Y-grafts can increase blood flow in response to an increase in myocardial oxygen consumption (MVO2). METHODS Twenty-seven patients who received complete arterial myocardial revascularization using the left internal thoracic artery (LITA) and the radial artery (RA) as composite Y-graft gave their consent to a pre-discharge coronary angiography and intravascular flow velocity measurements using a Doppler guide wire. Flow measurements were performed in the LITA main stem, the distal LITA and the RA, both at rest and during atrial pacing at the 85% of the patient age-predicted maximum. The heart rate-systolic blood pressure product was considered as an indirect index of MVO2. Hyperemic flow was determined after injection of adenosine. The flow reserve (FR) was defined as the ratio of blood flow during maximal hyperemia (Qmax) to baseline flow (Qbasal). RESULTS Atrial pacing increased MVO2 significantly (P<0.000). None of the patients developed ischemic S-T segment modifications or complained of chest pain. Q(basal) increased significantly in the LITA main stem (P=0.001), distal LITA (P=0.041) and RA (P=0.004) while Qmax did not change significantly. As a consequence, the FR decreased in the LITA main stem (P=0.002), distal LITA (P<0.000) and RA (P<0.000) but was not completely exhausted. CONCLUSIONS Soon after the operation, arterial composite Y-grafts can significantly increase blood flow in response to conditions of increased MVO2, keeping normal the myocardial O2 supply-to-demand ratio.

Bicuspid aortic valve: differences in the phenotypic continuum affect the repair technique

OBJECTIVE Bicuspid aortic valve (BAV) may be considered in the context of a phenotypic continuum of the aortic valve configuration, ranging from severe forms of unicuspid valve to rare forms of quadricuspid valve. In this article, we report our results with BAV repair using surgical techniques tailored to the specific features of the BAV phenotypic continuum. PATIENTS AND METHODS Between September 2003 and May 2009, 31 patients with BAV (mean age 49.9+/-17.3 years; five female; 26 male) were prospectively enrolled for aortic valve repair. The surgical strategy was tailored depending on the anatomical and structural characteristic of the BAV continuum: type 1 real bicuspid (five patients), type 2 bicuspid with raphe (24 patients) and type 3 clefted bicuspid (two patients). An echocardiographic analysis was performed preoperatively, postoperatively, at discharge and every 6 months during follow-up. Kaplan-Meier analysis was used to assess the freedom from re-operation. RESULTS One patient died in the intensive care unit due to aortic wall rupture. After BAV repair there was an increase of leaflet coaptation length (from 2.0+/-0.5 mm to 8.2+/-1.9 mm, p<0.01) and a decrease of the diameters of the virtual basal ring (from 24.6+/-3.6 mm to 21.5+/-0.71 mm, p<0.01), of the aortic root (from 43.12+/-13.23 mm to 31.0+/-3.2 mm, p<0.01) and of the sino-tubular junction (from 40.1+/-6.95 mm to 33.5+/-9.19 mm, p<0.05). The aortic regurgitation echocardiographic grade > or =II was found preoperatively in 30 patients and postoperatively in one patient (p<0.01). Six patients underwent an associated aortic valve-sparing procedure (three re-implantation and three remodelling). Kaplan-Meier analysis showed a 96.6% freedom from re-operation at 5 years, with a single new repair procedure and a 100% freedom from aortic valve replacement. CONCLUSIONS BAV repair provides a feasible therapeutic option in selected patients with good medium-term results. The surgical techniques should be applied after a careful analysis of the BAV considered in the context of the phenotypic continuum.

Intracardiac visualization of transcatheter aortic valve and valve-in-valve implantation in an in vitro passive beating heart.

![Figure][1] [Video 1][2] Standard TAVI procedure The movie shows the implantation of a 29 mm CoreValve, with views from both the left ventricle and the aorta. ![Figure][1] [Video 2][3] Valve-in-valve procedure The movie shows a valve-in-valve procedure, with a 26 mm CoreValve

A geometric approach to aortic root surgical anatomy

OBJECTIVES The aim of this study was the analysis of the geometrical relationships between the different structures constituting the aortic root, with particular attention to interleaflet triangles, haemodynamic ventriculo-arterial junction and functional aortic annulus in normal subjects. METHODS Sixteen formol-fixed human hearts with normal aortic roots were studied. The aortic root was isolated, sectioned at the midpoint of the non-coronary sinus, spread apart and photographed by a high-resolution digital camera. After calibration and picture resizing, the software AutoCAD 2004 was used to identify and measure all the elements of the interleaflets triangles and of the aortic root that were objects of our analysis. Multiple comparisons were performed with one-way analysis of variance for continuous data and with Kruskal-Wallis analysis for non-continuous data. Linear regression and Pearsons product correlation were used to correlate root element dimensions when appropriate. Students t-test was used to compare means for unpaired data. Herons formula was applied to estimate the functional aortic annular diameters. RESULTS The non coronary-left coronary interleaflets triangles were larger, followed by inter-coronary and right-non-coronary ones. The apical angle is <60° and its standard deviation can be considered an asymmetry index. The sinu-tubular junction was shown to be 10% larger than the virtual basal ring (VBR). The mathematical relationship between the haemodynamic ventriculo-arterial junction and the VBR calculated by linear regression and expressed in terms of the diameter was: haemodynamic ventriculo-arterial junction = 2.29 VBR (diameter) + 47. DISCUSSION Conservative aortic surgery is based on a better understanding of aortic root anatomy and physiology. The relationships among its elements are of paramount importance during aortic valve repair/sparing procedures and they can be useful also in echocardiographic analysis and in computed tomography reconstruction.

Intracardiac Visualization of Transcatheter Mitral Valve Repair in an In Vitro Passive Beating Heart

Transcatheter mitral valve repair has emerged as a feasible and safe alternative in patients with contraindications for surgery or high operative risk.1 Cardiac imaging plays a central role in selecting patients, guiding the procedure, and evaluating the durability of the repair at follow-up. Real-time 3-dimensional transesophageal echocardiography is a key point to visualize and optimize transcatheter mitral valve repair for a good result. However, the chance to clarify, …

Intraindividual comparison of human radial and internal thoracic arteries in vitro and the effect of preoperative calcium blocker therapy

The patency rate of radial artery (RA) conduits is considerably lower than that of internal thoracic artery (ITA) grafts and the evidence suggests that this is due to a clinically suspected higher incidence of vasospasm. The aim of this study was, therefore, to compare intraindividually the pharmacological reactivity of RA with that of ITA. Both RA and ITA were taken from the same patients and investigated in parallel. Changes in tone were monitored isometrically on ring preparations from both arteries in organ baths with modified Krebs–Henseleit solution containing 1.25 mm calcium chloride at 1 g passive preload. In intraindividual comparisons maximal receptor‐mediated contractile responses to noradrenaline and endothelin‐1 and endothelium‐dependent acetylcholine‐induced relaxant responses revealed no differences between both arteries. By contrast, depolarization‐induced contractions to potassium chloride (KCl) appeared to be significantly higher in RA than in ITA. Further analysis, however, revealed that this difference was due to preoperative calcium entry blocker (Ca2+eB) therapy. Compared with control tissues, maximal responses to KCl were significantly attenuated in the ITA but unchanged in RA when arteries were obtained from patients with preoperative Ca2+eB therapy. The present results suggested that functional responses to pharmacological stimuli of both RA and ITA were quite similar. Preoperative Ca2+eB therapy, however, attenuated markedly responses to KCl of the ITA leaving those of RA unchanged. These results, demonstrating a lower sensitivity to Ca2+eB of RA, therefore suggested that in addition to Ca2+eB other classes of drug may be more effective at reducing the propensity of RA conduits to vasospasm.