Etem Caliskan

Epicardial left atrial appendage AtriClip occlusion reduces the incidence of stroke in patients with atrial fibrillation undergoing cardiac surgery

Aims Left atrial appendage (LAA) occlusion has emerged as an interesting alternative to oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation (AF). We report the safety, efficacy, and durability of concomitant device-enabled epicardial LAA occlusion during open-heart surgery. In addition to long-term follow-up, we evaluate the impact on stroke risk in this selected population. Methods and results A total of 291 AtriClip devices were deployed epicardially in patients (mean CHA2DS2-VASc-Score: 3.1 ± 1.5) undergoing open-heart surgery (including isolated coronary artery bypass grafting, valve, or combined procedures) comprising of forty patients from a first-in-man device trial (NCT00567515) and 251 patients from a consecutive institutional registry thereafter. In all patients (n = 291), the LAA was successfully excluded and overall mean follow-up (FU) was 36 ± 23months (range: 1-97 months). No device-related complications were detected throughout the FU period. Long-term imaging work-up (computed tomography) in selected patients ≥5years post-implant (range: 5.1-8.1 years) displayed complete LAA occlusion with no signs of residual reperfusion or significant LAA stumps. Subgroup analysis of patients with discontinued OAC during FU (n = 166) revealed a relative risk reduction of 87.5% with an observed ischaemic stroke-rate of 0.5/100 patient-years compared with what would have been expected in a group of patients with similar CHA2DS2-VASc scores (expected rate of 4.0/100 patient-years). No strokes occurred in the subgroup with OAC. Conclusion The long-term results from our first-in-man prospective human trial plus our institutional registry of epicardial LAA occlusion with the AtriClip in patients with AF undergoing cardiac surgery demonstrate the safety and durability of the procedure. In addition, our data are suggestive for the potential efficacy of LAA occlusion in reducing the incidence of stroke. If validated in future large randomized trials, routine LAA occlusion in patients undergoing cardiac surgery (with contraindications to treatment with oral anticoagulants) may represent a reasonable adjunct procedure to reduce the risk of future stroke. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00567515.

Impact of a femoral snare approach as a bailout procedure on success rates in lead extractions

OBJECTIVES In cases of challenging transvenous lead extraction procedures, limitations exist for the subclavian approach (SCA). In case of absent alternative approaches, the procedure may end with failure. Therefore, we investigated the femoral snare approach (FSA) as bailout procedure. METHODS From December 2010 to August 2013, 114 patients with 190 leads were scheduled for transvenous lead extraction procedures [mean implant duration (MID): 74.7 (1-384) months]. In 28 leads [MID: 133.8 (36-384) months] the FSA was used. In 20 leads [MID: 127.5 (52-258) months] the FSA was performed as bailout approach and in 8 leads [MID: 149.6 (36-384) months] as first-line approach due to complete intravascular lead position. RESULTS In all FSA procedures (n = 28), clinical success was 85.7% and complete procedural success 64.3%. In FSA procedures as bailout approach (n = 20), clinical success was 80.0% and complete procedural success 55.0%. In first-line FSA procedures (n = 8), clinical success was 100.0% and complete procedural success 87.5%. Overall (n = 190) clinical success was 96.3%, complete procedural success 91.1%. By adding the FSA in cases of insufficient or impossible SCA, clinical success was increased by 12.6% (from 83.7 to 96.3%) and complete procedural success by 9.5% (from 81.6 to 91.1%). Comparison of leads extracted by SCA with leads extracted by FSA revealed that MID [133.8 (36-384) vs 64.4 (1-300) months; P < 0.0001] and the rate of passive fixation leads (67.9 vs 28.4%; P < 0.0001) were significantly higher in the FSA group. CONCLUSIONS In cases of failed or impossible subclavian approach, the femoral snare approach may improve overall success rates without relevantly increasing operative risk.

Clinical performance of a new bidirectional rotational mechanical lead extraction sheath

AIMS We investigated the safety and efficacy of a new bidirectional rotational mechanical extraction sheath (Evolution RL, Cook Medical, USA). METHODS AND RESULTS From April 2013 until September 2014, we performed lead extraction procedures in 71 patients with 112 leads scheduled for extraction. During this time period, we used the new Evolution RL rotational sheath in 40 patients on 52 leads (24 pacemaker leads and 28 implantable cardioverter-defibrillator leads) scheduled for extraction. The mean lead implant duration in these patients was 100.2 (22-271) months. Forty leads were right ventricular leads, 10 right atrial leads, and 2 coronary sinus leads. Clinical success among the leads approached with the Evolution RL device was 98.1%. Operative mortality was zero. Major complications did not occur. Four minor complications were encountered (all pocket haematomas). No device-related complications were noted. In cases with multiple leads in situ, no wrapping of companion leads was seen. The average number of extraction tools used per lead was 2.4 (2-4) in the Evolution RL cohort. CONCLUSION Based on the presented results of our initial experience with the new bidirectional rotational mechanical extraction device, its use is safe and efficient with high success rates in long implanted leads.

Long-term follow-up after aortic root replacement with the Shelhigh® biological valved conduit: a word of caution!

OBJECTIVES The aim of this study was to analyse long-term results of aortic root replacement with the Shelhigh® NR-2000C conduit. METHODS From January 2001 to October 2005, 63 patients with a median age of 62 years underwent aortic root replacement with a Shelhigh® conduit. Aneurysm (27%), aortic valve endocarditis (30%) and acute type A aortic dissection (33%) were the predominant indications for the surgery. Fifty-four patients (86%) were entered in the follow-up study with the end-points of death, aortic root-related reoperation and endocarditis. RESULTS The overall 30-day mortality rate was 8% (n = 5). The median follow-up was 9.5 years (range 0-14.2 years). In total, 13 (24%) deaths occurred during follow-up; of these, 4 were directly conduit-related. The overall estimated survival rates at 1, 5 and 10 years were 85 ± 5, 79 ± 6 and 71 ± 7%, respectively. Reoperation was necessary in 10 (19%) patients due to endocarditis (n = 5), aortic stenosis (n = 3), pseudoaneurysm due to detachment of the right coronary artery (n = 1) and detachment of the non-coronary leaflet (n = 1). The overall estimated rate of freedom from aortic root-related reoperation at 1, 5 and 10 years was 83 ± 5, 79 ± 6 and 64 ± 7%, respectively. Endocarditis of the prosthesis was reported in 9 (17%) patients; of whom, 5 patients required reoperation and 4 were treated medically. In 1 patient with endocarditis, a stroke was reported due to a thromboembolic event. CONCLUSIONS The first long-term follow-up after aortic root replacement with the Shelhigh® BioConduit revealed a relatively high rate of death and very high rate of reoperations due to endocarditis, aorto-ventricular disconnection and structural valve failure. This may be potentially connected to the nature of the implanted valved conduit.

Interventional and surgical occlusion of the left atrial appendage

With a steadily increasing prevalence, atrial fibrillation (AF) is the most common sustained cardiac arrhythmia worldwide and an independent risk factor for stroke caused by thromboembolic events. The left atrial appendage (LAA) is the primary source of thromboemboli in patients with nonvalvular AF who have a stroke. Novel strategies (such as mechanical and nonpharmacological intervention) targeting the LAA in patients with AF for stroke prevention have become a major focus during the past decade. Some devices for percutaneous LAA occlusion are supported by robust clinical data obtained from randomized trials or large registries, and are a valid alternative to pharmacological stroke prevention. However, the incidence of periprocedural complications and the presence of device-related thrombi or residual LAA leaks, whose long-term clinical implications are still unknown, are limiting factors in wider acceptability of these techniques. In this Review, we discuss the available techniques for LAA occlusion in patients with nonvalvular AF at high risk of stroke. We describe the pharmacological and mechanical approaches to LAA occlusion, and provide the current clinical evidence for various strategies. We particularly focus on the current management of the LAA, and discuss the challenges and future implications of the available approaches to LAA occlusion.

Extracellular matrix for reconstruction of cardiac structures after tumour resections

OBJECTIVES To describe the use of a new extracellular matrix patch as a means for atrial reconstruction in patients with cardiac tumours. METHODS A new extracellular matrix patch was used to reconstruct atrial and neighbouring structures after tumour resections. In 1 case, it was used to reconstruct the atrial septum and the left atrial roof after excision of a huge myxoma. In a second case, it was used to reconstruct the right atrium, including the superior vena cava after excision of a primary cardiac sarcoma. In a third case, it was used to reconstruct both atria, the right-sided pulmonary venous confluence and the roof of the coronary sinus after excision of a metastasis of malignant melanoma. RESULTS In all cases, reconstruction was successful and facilitated because of the flexible and thin character of the extracellular matrix, which also seemed to be advantageous with regards to haemostasis. CONCLUSIONS Extracellular matrix patches are a potential alternative for pericardial patches for complex reconstructions of atrial structures because of their pliable characteristics and consecutively reduced need for haemostatic stitches.

Survival, Neurologic Injury, and Kidney Function after Surgery for Acute Type A Aortic Dissection.

BACKGROUND To analyze survival, neurologic injury, and kidney function after acute type A aortic dissection. METHODS A total of 445 patients undergoing surgery for acute type A aortic dissection were analyzed. Evaluation according to risk factors for mortality, neurologic injury, and kidney function was performed. RESULTS Overall 1-, 5-, and 10-year survival rates were 82.8 ± 1.8%, 73.6 ± 2.4%, and 59.3 ± 3.9, respectively. Independent preoperative risk factors for mortality were preexisting renal impairment (p = 0.001), reduced left ventricular ejection fraction (p < 0.001), and age (p < 0.001). Perioperative risk factors were prolonged cross-clamp (p < 0.001) and cerebral perfusion time (p = 0.001). Risk factors for renal failure were preexisting renal impairment (p < 0.001), prolonged cross-clamp time (p < 0.001), cerebral perfusion time (p < 0.001), and age (p = 0.022). Risk factors for neurologic injury were cross-clamp time (p = 0.038), cerebral perfusion time (p = 0.007), and age (p = 0.045). CONCLUSION In addition to classic risk factors, survival after type A aortic dissection is affected by preexisting renal impairment. Preexisting renal impairment is predictive of postoperative renal failure. Therefore treatment and prevention strategies for renal failure during the acute and long-term course after acute type A aortic dissection are warranted.

Left anterior small thoracotomy for minimally invasive coronary artery bypass grafting.

Since the 1990 s, minimally invasive cardiac surgery has gained wide acceptance due to patient and economic demand. The advantages are less trauma, bleeding, wound infections, pain and faster recovery. Many studies showed that the outcomes are comparable with those of conventional sternotomy. Left anterior small thoracotomy (LAST) evolved into a routine and safe access in specialized centres for minimally invasive direct coronary artery bypass grafting. The 6-cm incision is localized above the fourth intercostal space, 3-4 cm lateral to the left sternal border and below the left mammilla. With a double-lumen tube, the left lung is deflated before entering the pleural space. The left internal mammary artery is harvested under direct vision with the use of special retractors. The anastomosis of the left anterior descending artery is performed on the beating heart as known from off-pump surgery. One chest tube is inserted. The intercostal space is closed with braided sutures to prevent lung herniation. Ropivacaine is used for local infiltration. The pectoral muscle, subcutaneous tissue and skin are closed with running sutures. Complications of the LAST approach are rare (conversion to sternotomy, re-thoracotomy, phrenic nerve palsy, wound infection and thoracic wall hernia) and well manageable.

The Potential Impact of Functional Imaging on Decision Making and Outcome in Patients Undergoing Surgical Revascularization

OBJECTIVE Coronary angiography (CA) remains the standard for preoperative planning for surgical revascularization. However, besides anatomical imaging, current guidelines recommend additional functional imaging before a therapy decision is made. We assess the impact of functional imaging on the strategy of coronary artery bypass grafting (CABG) with particular regards on postoperative patency and myocardial perfusion. METHODS After CA, 55 patients (47 males/8 females; age: 65.1 ± 9.5 years) underwent perfusion cardiovascular magnetic resonance (CMR) and dual-source computed tomography (DSCT) before isolated CABG (n = 31), CABG and concomitant valve surgery (valve + CABG; n = 10) and isolated valve surgery (n = 14; control). DSCT was used for analysis of significant stenosis, CMR for myocardial-perfusion to discriminate between: no ischemia (normal), ischemia, or scar. The results, unknown to the surgeons, were compared with CA and related to the location and number of distal anastomoses. Nineteen CABG patients underwent follow-up CMR and DSCT (FU: 13 ± 3 months) to compare the preop findings with the postop outcomes. RESULTS Thirty-nine patients either received CABG alone (n = 31) or a combined procedure (n = 10) with a total of 116 distal anastomoses. DSCT was compared with CA regarding accuracy of coronary stenosis and showed 91% sensitivity, 88% specificity, and negative/positive predictive values of 89/90%. In total, 880 myocardial segments (n = 55, 16 segments/patient) were assessed by CMR. In 17% (149/880) of segments ischemia and in 8% (74/880) scar tissue was found. Interestingly, 14% (16/116) of bypass-anastomoses were placed on non-ischemic myocardium and 3% (4/116) on scar tissue. In a subgroup of 19 patients 304 segments were evaluated. Thirty-nine percent (88/304) of all segments showed ischemia preoperatively, while 94% (83/88) of these ischemic segments did not show any ischemia postoperatively. In regard to performed anastomoses, 79% of all grafts (49/62) were optimally placed, whereas 21% (13/62) were either placed into non-ischemic myocardium or scar tissue, including 10% occluded grafts (6/62). CONCLUSION In the whole cohort analysis, 17% of grafts were placed in regions with either no ischemia or scar tissue. The subgroup analysis revealed that 94% of all ischemic segments were successfully revascularized after CABG. Thus, functional imaging could be a promising tool in preoperative planning of revascularization strategy. Avoidance of extensive and unnecessary grafting could further optimize outcomes after CABG.

Development of a Novel Human Cell-Derived Tissue-Engineered Heart Valve for Transcatheter Aortic Valve Replacement: an In Vitro and In Vivo Feasibility Study

Transcatheter aortic valve replacement (TAVR) is being extended to younger patients. However, TAVR-compatible bioprostheses are based on xenogeneic materials with limited durability. Off-the-shelf tissue-engineered heart valves (TEHVs) with remodeling capacity may overcome the shortcomings of current TAVR devices. Here, we develop for the first time a TEHV for TAVR, based on human cell-derived extracellular matrix and integrated into a state-of-the-art stent for TAVR. The TEHVs, characterized by a dense acellular collagenous matrix, demonstrated in vitro functionality under aortic pressure conditions (n = 4). Next, transapical TAVR feasibility and in vivo TEHV functionality were assessed in acute studies (n = 5) in sheep. The valves successfully coped with the aortic environment, showing normal leaflet motion, free coronary flow, and absence of stenosis or paravalvular leak. At explantation, TEHVs presented full structural integrity and initial cell infiltration. Its long-term performance proven, such TEHV could fulfill the need for next-generation lifelong TAVR prostheses.