Dimitrios Buklas

Cerebral autoregulation after hypothermic circulatory arrest in operations on the aortic arch.

BACKGROUND The purpose of this study was to determine whether patients who undergo thoracic aorta repairs with the aid of hypothermic circulatory arrest experience impairments in cerebral autoregulation, and to ascertain the influence of three different techniques of cerebral protection on autoregulatory function. METHODS Sixty-seven patients undergoing elective aortic arch procedures with hypothermic circulatory arrest were tested for cerebral dynamic autoregulation using continuous transcranial Doppler velocity and blood pressure recordings. Twenty-three patients were treated using hypothermic circulatory arrest without adjuncts (group 1), 25 using antegrade cerebral perfusion (group 2), and 19 using retrograde cerebral perfusion (group 3). RESULTS There were no hospital deaths. Two major strokes occurred in this series; 9 patients experienced temporary neurologic dysfunction: in all these patients severe impairment of cerebral autoregulation was observed. Cerebral autoregulation in the immediate postoperative period was preserved only in patients treated with antegrade cerebral perfusion. Severe impairments were observed in the other two groups in which the degree of autoregulatory response was inversely correlated to the duration of the cerebral protection time during hypothermic circulatory arrest. Postoperative improvement of autoregulatory function was observed in the majority of patients. Our data suggest the exposure to brain damage in the presence of autoregulation impairment, thus indicating that postoperative hypotensive phases may further contribute to neurologic impairment. CONCLUSIONS The status of cerebral autoregulation in the postoperative period after hypothermic circulatory arrest procedures is profoundly altered. The degree of impairment is influenced by the cerebral protection technique. This study indicates the beneficial role of antegrade perfusion during hypothermic circulatory arrest for the preservation of this function and suggests that postoperative cerebral autoregulation impairment can be regarded as an expression of central nervous system injury.

Octreotide for recurrent intestinal bleeding due to ventricular assist device

We report the case of a 64-year-old Jarvik 2000 recipient with a high risk of bleeding (anticoagulation treatment and acquired von Willebrand disease), who presented with intractable gastrointestinal hemorrhage due to severe gastric angiodysplasia. He was successfully treated with long-acting octreotide.

Built-in defect of a biological pericardial aortic prosthesis?

We report a case on an early complication of a biological pericardial tissue valve in the aortic position that required emergency replacement. One of the three leaflets of the valve was stuck open in a fixed-open position and would not unfold in diastole. This resulted in severe aortic insufficiency, diagnosed by standard postoperatory echocardiography and confirmed in the operating room.

Surgical treatment of abdominal aortic aneurysms associated with aortic valve incompetence: strategies and outcomes.

BACKGROUND The exact incidence of associated aortic valve incompetence (AVI) and abdominal aortic aneurysm (AAA) in the general population is not known. In recent years, we have observed this association with increasing frequency. This observation is probably due to the extensive preoperative screening of the cardiac and vascular status of patients who are candidates for surgical procedures. The choice of the optimal surgical strategy is needed to achieve low operative morbidity and mortality. The present study reviews our experience with a subset of patients suffering the association of AVI and large AAA. Surgical strategy, clinical management and outcome are presented. METHODS Between January 1982 and May 2000, 76 patients with the association of AAA and AVI have been evaluated in our institution. Forty-four patients have been treated for both AAA and aortic valve (AV) regurgitation. These patients have been divided into three groups on the basis of the surgical strategy adopted. Group 1: combined procedure (16 patients); group 2: AAA repair prior to AV surgery (nine patients); group 3: AV surgery prior to aneurysm repair (19 patients). RESULTS Hospital mortality was 4.5% (two patients); overall mortality was 6.8% (three patients). CONCLUSIONS In patients with AAA and AVI, an accurate and complete preoperative evaluation is essential. Surgical strategy should be individualized on the basis of the cardiac preoperative status.

Angioplasty balloon catheter entrapment.

An 81-year-old man was treated by inserting a Rotablator and a drug-eluting stent (Promus 3.0 38 mm stent; Boston Scientific) for calcified left anterior descending coronary artery stenosis. During inflation, the balloon catheter broke and was retained within the stent. (Figure 1). An emergency surgical transaortic balloon retrieval was performed with coronary artery bypass grafting (Figure 2; Video 1). The patient was doing well 1year later. Funding

Less invasive radial artery harvesting: two years' experience.

BACKGROUND For coronary surgery we often use the radial artery (RA) instead of the saphenous vein, trying to exploit the advantages offered by this conduit. To eliminate the problems regarding alteration of upper-extremity function after RA procurement related to the standard conventional harvesting technique, we started using the less invasive harvesting technique with surprisingly good preliminary results. To compare the outcomes of open versus less invasive harvesting procedures, a prospective, nonrandomized study was developed by 2 centers. METHODS From January 2001 to March 2003, there were 87 consecutive patients in the less invasive radial artery harvesting (LIRAH) group and 90 patients in the conventional radial artery harvesting (CRAH) group. Patient characteristics and demographics were similar in the groups. Data collection was made to evaluate possible benefits of the LIRAH technique in terms of fewer forearm and hand complications, better aesthetics, and improved patient satisfaction. RESULTS Between January 11, 2001, and March 30, 2003, 177 patients underwent either primary or redo coronary artery revascularizations with procurement of the RA for use as a conduit with the less invasive harvesting technique. The mean follow-up was 2 months. Four patients died, and overall mortality was 2.26%. One hundred seventy-three patients were successfully examined during the first postoperative control, 85 in the LIRAH group and 88 patients in the CRAH group. Objective and subjective data were collected from the consultant. The overall average age was 60.5 years (range, 40-77 years). In the LIRAH group, the mean overall incision length (when 2 incisions were necessary, both incision lengths were measured) was 5.6 cm (range, 4-10 cm), and the mean vessel length was 16 cm (range, 10-19 cm). Eighteen patients (20.6%) necessitated double incision. Mean harvesting time (from incision to skin closure) was 43.3 min (range, 25-70 min). Fourteen patients (16.4%) presented some kind of complication during the study. There were no cases with acute ischemia, bleeding, or re-exploration. Seventy-five patients (88.2%) found the cosmetic result excellent. Ten patients (11.8%) found it good, and none considered it mediocre. In the CRAH group, the mean incision length was 20 cm (range, 18-22 cm), and the mean vessel length was 18 cm (range, 17-20 cm ). Mean harvesting time (from incision to skin closure) was 30.8 min (range, 14-45 min). Thirty-four patients (38.6%) presented some kind of complication during the study. Three patients (3.5%) found the cosmetic result excellent. Forty-three (48.8%) found it good, and 42 (47.7%) considered it mediocre. CONCLUSIONS A potential of fewer neurological forearm postoperative complications, better aesthetics, and improved patient satisfaction can be achieved by the LIRAH technique.

Predicting Survival After Extracorporeal Membrane Oxygenation for ARDS: An External Validation of RESP and PRESERVE Scores

BACKGROUND: We aimed to test the performance of PRESERVE and RESP scores to predict death in patients with severe ARDS receiving extracorporeal membrane oxygenation (ECMO) with different case mixes. METHODS: All consecutive patients treated with ECMO for refractory ARDS, regardless of cause, in the Caen University Hospital in northwestern France over the last decade were included in a retrospective cohort study. The receiver operating characteristic curves of each score were plotted, and the area under the curve was computed to assess their performance in predicting mortality (c-index). RESULTS: Forty-one subjects were included. Pre-ECMO ventilator settings were: mean VT, 6.1 ± 0.9 mL/kg; breathing frequency, 32 ± 4 breaths/min; PEEP, 11 ± 4 cm H2O; peak inspiratory pressure, 48 ± 9 cm H2O; plateau pressure, 30.4 ± 4.4 cm H2O. At ECMO initiation, blood gas results were: pH 7.22 ± 0.17, PaO2/FIO2 = 63 ± 22 mm Hg; PaCO2 = 56 ± 18 mm Hg; FIO2 = 99 ± 2%. Pre-ECMO data were available in 35 and 27 subjects for calculation of the PRESERVE score and RESP score, respectively. Pre-ECMO scoring system results were: median PRESERVE score, 4 (interquartile range 2–5), and median RESP score, 0 (interquartile range −2 to 2). Twenty-three subjects (56%) died, including 19 receiving ECMO. In univariate analysis, plateau pressure (P = .031), driving pressure (P = <.001), and compliance (P = .02) recorded at the time of ECMO initiation as well as the PRESERVE score (P = .032) were significantly associated with mortality. With a c-index of 0.69 (95% CI 0.53–0.87), the PRESERVE score had better discrimination than the RESP score (c-index of 0.60 [95% CI 0.41–0.78]) for predicting mortality. CONCLUSIONS: The use of these scores in helping physicians to determine the patients with ARDS most likely to benefit from ECMO should be limited in clinical practice because of their relatively poor performance in predicting death in subjects with severe ARDS receiving ECMO support. Before widespread use is initiated, these scoring systems should be tested in large prospective studies of subjects with severe ARDS undergoing ECMO treatment.

Stentless bioprosthesis for treatment of traumatic aortic valve rupture

Aortic valve rupture after blunt trauma to the chest is an infrequent complication that should be considered at the outset in examination of an accident victim. The presence of aortic regurgitation with hemodynamic instability is an indication for surgery. We implanted a stentless bioprosthesis after aortic valve rupture due to chest trauma in a 31-year-old man with schizophrenia.

Right origin of the circumflex artery and posterior aortic annulus enlargement

We present the case of a patient who required posterior enlargement of the aortic annulus during aortic valve replacement in the presence of abnormal origin of the circumflex artery from the right coronary artery, with a retroaortic course.

Ascending aorta thrombosis in a HeartWare® left ventricular assist device recipient.

Supplementary material (Video S1 and Video S2) is available at EJCTS online. Video 1: Aortic angiography and computed tomography view of the aortic thrombus. Video 2: Perioperative view of HeartWare implantation and morpho-pathological aspects of the explanted heart. Figure 1: Computed tomography (CT) image of the aortic thrombus. One month after the left ventricular assist device implantation, the patient underwent in situ right middle cerebral artery fibrinolysis for embolic stroke. Cardiac echography showed the absence of any intracardiac thrombus. Five days later, multiples episodes of ventricular fibrillation occurred. Aortic angiography and echocardiography showed a complete thrombosis of the left Valsalva sinus, which was resistant to medical treatment. CT examination confirmed the presence of the thrombus. Figure 2: Morphopathological view of the thrombus on the explanted heart after transplantation (showing a left main coronary trunk thrombosis). The patient was transplanted emergently, but died a few days later from multiorgan failure.