Loris Salvador

A 20-year experience with mitral valve repair with artificial chordae in 608 patients

OBJECTIVE Mitral valve repair with artificial chordae for degenerative mitral regurgitation is widely adopted. We evaluated long-term results of mitral repair with expanded polytetrafluoroethylene sutures (GORE-TEX CV-5; W. L. Gore & Associates, Inc, Flagstaff, Ariz). METHODS Between November 1986 and November 2006, 608 consecutive patients underwent mitral repair with artificial neochordae. Mean age was 55 +/- 11 years (15-85 years); 433 (71.2%) were male. Valve disease was purely degenerative in 555 patients (91.3%). Prolapse of anterior, posterior, or both leaflets was present in 47 (7.7%), 308 (50.7%), and 253 (41.6%), respectively. Atrial fibrillation was associated in 117 (19.2%). In 125 cases (20.5%), additional surgical procedures were performed. Follow-up was complete at a median of 5.7 years (interquartile range 2.2-9.8 years, range 0-19.4 years). RESULTS In-hospital mortality was less than 1% (6 deaths). Overall and cardiac late mortalities were 6.6% and 3.9% (34 and 24 deaths). Kaplan-Meier survival at 15 years was 84% (95% confidence interval 75%-90%). Freedoms from endocarditis, thromboembolic events, reoperation, and recurrent mitral regurgitation at 15 years were 97% (95% confidence interval 93%-99%), 92% (87%-95%), 92% (88%-95%), and 85% (78%-91%), respectively. Sinus rhythm was restored in 75% (33 patients) after surgical atrial fibrillation correction. Calcification of GORE-TEX neochordae was never reported. CONCLUSION Mitral valve repair with GORE-TEX artificial chordae is effective, safe, and associated with low operative mortality and low rates of valve-related complications at long-term follow-up. Artificial chordae showed excellent biologic adaptation, retaining flexibility and tension with time.

Clinical and hemodynamic outcomes of ''all-comers'' undergoing transapical aortic valve implantation: Results from the Italian Registry of Trans-Apical Aortic Valve Implantation (I-TA)

OBJECTIVE The aim of this study was to assess clinical and hemodynamic outcomes of transapical aortic valve implantation (TA-TAVI) in patients enrolled in the Italian Registry of Trans-Apical Aortic Valve Implantation (I-TA). METHODS From April 2008 until November 2010, 504 patients from 20 Italian centers were enrolled in the I-TA registry. Mean logistic EuroSCORE and Society of Thoracic Surgeons score were 24% ± 16% and 11% ± 4%, respectively. Mean follow-up was 9.2 ± 6.5 months (range, 1-26 months). Outcomes were analyzed according to intraoperative complications, procedural volume (high-volume centers, >20 cases; low-volume centers, < 20 cases) and learning curve (first 50% cases vs second 50% cases of each center). RESULTS All-cause overall mortality was 8.3% (42 patients). Device success was 99% (500/504 patients). Intraoperative severe complications occurred in 24 (4.8%) patients. Overall 2-year survival was 71.5% ± 6.2%. At discharge, peak and mean gradients were 16.4 ± 11.2 and 8.7 ± 4.1 mm Hg, respectively, and effective orifice area was 1.67 cm(2). These values remained stable at 3, 6, and 12 months after surgery. Independent risk factors for mortality after TA-TAVI were as follows: New York Heart Association class III and IV (odds ratio [OR], 4.43; 95% confidence intervals [CI], 1.28-15.40; P = .02); logistic EuroSCORE greater than 20 (OR, 1.83; 95% CI, 1.02-3.29; P = .04); creatinine concentration greater than 200 μmol/L (OR, 2.56; 95% CI, 1.07-6.15; P = .03), and intraoperative complications (OR, 5.80; 95% CI, 2.68-12.55; P < .001). There were no significant differences in outcomes between high- and low-volume centers and between the first and the second 50% of cases. CONCLUSIONS TA-TAVI represents a safe and effective alternative treatment for patients who are inoperable or at high risk for surgery. The occurrence of an intraoperative complication significantly affects survival. Procedural volume and learning curve have no impact on patient survival.

The fate of Hancock II porcine valve recipients 25 years after implant

OBJECTIVE The Hancock II (HII) is a second-generation porcine bioprosthesis introduced into clinical use in 1982. This study aimed to evaluate very long-term outcomes for the HII valve in a large patient population. METHODS Between May 1983 and November 1993, 517 consecutive patients (pts) (309 male, mean age: 64+/-9 years) underwent valve replacement (VR) surgery with HII, with 302 (58.4%) in the aortic VR (AVR) and 215 (41.6%) in the mitral VR (MVR) position, respectively. At implant, 106 pts (20.5%) were <60 years of age (G1), while 411 (79.5%) were > or =60 years of age (G2). The 25-year follow-up was complete for all pts at a median of 12 years (range: 0-25). RESULTS Long-term death occurred in 208 AVR and in 165 MVR pts. Survival at 15 and 20 years was 39.5% and 23.3% in AVR pts and 39.0% and 15.8% in MVR pts. At 25 years the survival of MVR pts was 13.7% (four pts at risk). Late freedom from re-operation was 85.5% and 79.3% at 15 and 20 years in the AVR pts and 73.3% and 52.8% in the MVR pts, respectively. In the AVR population, 20-year freedom from re-operation was 52.2% in G1 pts and 86.8% in G2 pts (p<0.0001), while in the MVR population it was 41.4% in G1 pts and 61.9% in G2 pts (p=0.201), respectively. CONCLUSIONS These results confirm the excellent long-term performance of the HII bioprosthesis.

Cardiac surgery-associated acute kidney injury.

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common and serious postoperative complication of cardiac surgery requiring cardiopulmonary bypass (CPB), and it is the second most common cause of AKI in the intensive care unit. Although the complication has been associated with the use of CPB, the etiology is likely multifactorial and related to intraoperative and early postoperative management including pharmacologic therapy. To date, very little evidence from randomized trials supporting specific interventions to protect from or prevent AKI in broad cardiac surgery populations has been found. The definition of AKI employed by investigators influences not only the incidence of CSA-AKI, but also the identification of risk variables. The advent of novel biomarkers of kidney injury has the potential to facilitate the subclinical diagnosis of CSA-AKI, the assessment of its severity and prognosis, and the early institution of interventions to prevent or reduce kidney damage. Further studies are needed to determine how to optimize cardiac surgical procedures, CPB parameters, and intraoperative and early postoperative blood pressure and renal blood flow to reduce the risk of CSA-AKI. No pharmacologic strategy has demonstrated clear efficacy in the prevention of CSA-AKI; however, some agents, such as the natriuretic peptide nesiritide and the dopamine agonist fenoldopam, have shown promising results in renoprotection. It remains unclear whether CSA-AKI patients can benefit from the early institution of such pharmacologic agents or the early initiation of renal replacement therapy.

Pathological biominerals: Raman and infrared studies of bioapatite deposits in human heart valves

We studied pathological bioapatite from patients undergoing valvular replacement due to severe aortic and mitral stenosis. Three different types of mineralized human cardiac valves were analyzed. We used infrared and Raman spectroscopy to infer the presence of the carbonate group and evaluate the carbonate substitution in bioapatite structure. The Raman spectra showed that the pathological bioapatite is a B-type “carbonateapatite” (CO32- for PO43-) similar to the major mineralized products derived from normal biomineralization processes occurring in the human body. Fourier transform infrared spectra (FT-IR) confirmed the B-type carbonate substitution (CO32- for PO43-) and showed evidence for the partial replacement of [OH] by [CO3] (A-type substitution). The carbonate content of the samples inferred by the spectroscopic measurements is in good agreement with the range of values estimated for biological apatite. On the contrary, the crystal size of the pathological apatite estimated using the percentage area of the component at 1059 cm−1 of the infrared spectrum is in the nanometer range and it is significantly smaller than the crystal size of normal mineralized tissues.

Microembolic signals and strategy to prevent gas embolism during extracorporeal membrane oxygenation

BackgroundExtracorporeal membrane oxygenation (ECMO) supplies systemic blood perfusion and gas exchange in patients with cardiopulmonary failure. The current literature lacks of papers reporting the possible risks of microembolism among the complications of this treatment.In this study we present our preliminary experience on brain blood flow velocity and emboli detection through the transcranial Doppler monitoring during ECMO.MethodsSix patients suffering of heart failure, four after cardiac surgery and two after cardiopulmonary resuscitation were treated with ECMO and submitted to transcranial doppler monitoring to accomplish the neurophysiological evaluation for coma.Four patients had a full extracorporeal flow supply while in the remaining two patients the support was maintained 50% in respect to normal demand.All patients had a bilateral transcranial brain blood flow monitoring for 15 minutes during the first clinical evaluation.ResultsMicroembolic signals were detected only in patients with the full extracorporeal blood flow supply due to air embolism.ConclusionsWe established that the microembolic load depends on gas embolism from the central venous lines and on the level of blood flow assistance.The gas microemboli that enter in the blood circulation and in the extracorporeal circuits are not removed by the membrane oxygenator filter.Maximum care is required in drugs and fluid infusion of this kind of patients as a possible source of microemboli. This harmful phenomenon may be overcome adding an air filter device to the intravenous catheters.

Modified Button-Bentall Operation for Aortic Root Replacement: The Miniskirt Technique

BACKGROUND The aim of this study was to evaluate the midterm results of a modified button-Bentall operation (modified-bB) specifically designed to incorporate any type of prosthetic valve in composite conduit aortic root replacement. METHODS Between 1991 and 2000, a total of 135 patients underwent modified-bB for annuloaortic ectasia (74 patients), type A dissection (31), or aortic aneurysm without dissection (30). Of these, 34 were emergencies (25.2%). A total of 50 bioprostheses (study group 1) and 85 bileaflet mechanical prostheses (study group 2) were implanted. Group 1 mean age was 66.9 +/- 7.4 years versus 51.5 +/- 12.1 years in group 2 (p < 0.001). Composite-conduit creation occurred during proximal suture line construction as a single-step maneuver. Interrupted extracardiac polyester mattress sutures sequentially entered the aortic annulus, the prosthetic valve ring, and the vascular graft 7 mm from its free edge (miniskirt). Running monofilament suture line secured proximal hemostasis, buttressing aortic remnants and graft edge. Coronary reimplantation was accomplished in all cases by the button technique. Concomitant procedures were performed in 51 patients (37.8%). RESULTS The 30-day mortality was 5.18% (7/135 patients). Eight patients (5.9%) required revision for proximal (1 patient), coronary button (3), or distal (4) anastomosis leakage. Three patients (2.2%) perioperatively developed nonfatal inferior myocardial infarction. Kaplan-Meier 9-year survival is 91.8% +/- 0.026 SE with 88.1% (95% confidence limits 71.7% to 95.5%) reoperation freedom. According to the Cox proportional hazard method, stratification of the risk for death according to prosthesis type indicates previous operation (p = 0.001) and emergency (p = 0.0465) as independent predictors of hospital mortality. Associated procedures to modified-bB increased risk of reoperation (p = 0.031). CONCLUSIONS Modified-bB was associated with low mortality, excellent midterm survival, and freedom from reoperation. Absence of valve-to-graft tapering, reduced coronary button anastomosis tension, and prosthesis selection according to patient profile, are apparent advantages of modified-bB.

Transapical aortic valve implantation in high-risk patients with severe aortic valve stenosis.

BACKGROUND Transapical aortic valve implantation (TA-TAVI) represents an alternative in patients with symptomatic severe aortic valve stenosis (SSAVS) who cannot be operated on or have a high surgical risk. The aim of this prospective multicenter observational study was to assess early and 2-year clinical and hemodynamic outcomes after TA-TAVI. METHODS From May 2008 to September 2010, 179 patients with inoperable conditions or high-risk patients underwent TA-TAVI at 4 institutions. Indications for TA-TAVI were SSAVS and logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) greater than 20% or porcelain aorta in patients with severe aortoiliac disease. Patients underwent clinical and echocardiographic follow-up visits at hospital discharge, 3 and 6 months after TA-TAVI, and every 6 months thereafter. The impact of the learning curve for the centers and of intraoperative complications on patient outcomes was also evaluated. RESULTS Mean age was 81 ± 6 years. Mean logistic EuroSCORE was 22% ± 12%. Transapical delivery was successful in all patients. Seventeen severe intraoperative complications occurred in 13 (7.3%) patients. Thirty-day mortality was 3.9% (7 patients). Mean follow-up was 9.2 ± 6.5 months. Late mortality occurred in 9 patients. Two-year survival was 88% ± 3%. An intraoperative severe complication was identified as the only significant independent predictor of 1-year mortality. A significant benefit was found when comparing 2-year survival of the second versus the first 50% patients at each center (93% ± 2% versus 84% ± 3 %; p = 0.046). A significant reduction of both mean and peak gradients from the preoperative to the postoperative period, which remained stable during follow-up, was found. CONCLUSIONS TA-TAVI provides excellent early and 2-year results in terms of survival, valve-related adverse events, and hemodynamic performance. Survival after TA-TAVI is affected by the center learning curve and by the occurrence of an intraoperative complication.

Left Atrial Wall Hematoma as a Consequence of Percutaneous Coronary Angioplasty

Intramural left atrial dissection and hematoma as a complication of a coronary stenting procedure is a very rare entity. We report the case of a 73-year-old man who underwent percutaneous coronary angioplasty for a severe stenosis of the left circumflex coronary artery, complicated by a left atrial intramural hematoma, and was successfully treated with via a minimally invasive port-access surgical approach.

Morphological and Chemical Study of Pathological Deposits in Human Aortic and Mitral Valve Stenosis: A Biomineralogical Contribution

Aim of this study was to investigate heart valve calcification process by different biomineralogical techniques to provide morphological and chemical features of the ectopic deposit extracted from patients with severe mitral and aortic valve stenosis, to better evaluate this pathological process. Polarized light microscopy and scanning electron microscopy analyses brought to light the presence of nodular and massive mineralization forms characterized by different levels of calcification, as well as the presence of submicrometric calcified globular cluster, micrometric cavities containing disorganized tissue structures, and submillimeter pockets formed by organic fibers very similar to amyloid formations. Electron microprobe analyses showed variable concentrations of Ca and P within each deposit and the highest content of Ca and P within calcified tricuspid aortic valves, while powder X-ray diffraction analyses indicated in the nanometer range the dimension of the pathological bioapatite crystals. These findings indicated the presence of highly heterogeneous deposits within heart valve tissues and suggested a progressive maturation process with continuous changes in the composition of the valvular tissue, similar to the multistep formation process of bone tissue. Moreover the micrometric cavities represent structural stages of the valve tissue that immediately precedes the formation of heavily mineralized deposits such as bone-like nodules.