Jacek Bednarek

Percutaneous left atrial appendage suture ligation using the LARIAT device in patients with atrial fibrillation: initial clinical experience.

OBJECTIVES The purpose of the study was to determine the efficacy and safety of left atrial appendage (LAA) closure via a percutaneous LAA ligation approach. BACKGROUND Embolic stroke is the most devastating consequence of atrial fibrillation. Exclusion of the LAA is believed to decrease the risk of embolic stroke. METHODS Eighty-nine patients with atrial fibrillation were enrolled to undergo percutaneous ligation of the LAA with the LARIAT device. The catheter-based LARIAT device consists of a snare with a pre-tied suture that is guided epicardially over the LAA. LAA closure was confirmed with transesophageal echocardiography (TEE) and contrast fluoroscopy immediately, then with TEE at 1 day, 30 days, 90 days, and 1 year post-LAA ligation. RESULTS Eighty-five (96%) of 89 patients underwent successful LAA ligation. Eighty-one of 85 patients had complete closure immediately. Three of 85 patients had a ≤ 2-mm residual LAA leak by TEE color Doppler evaluation. One of 85 patients had a ≤ 3-mm jet by TEE. There were no complications due to the device. There were 3 access-related complications (during pericardial access, n = 2; and transseptal catheterization, n = 1). Adverse events included severe pericarditis post-operatively (n = 2), late pericardial effusion (n = 1), unexplained sudden death (n = 2), and late strokes thought to be non-embolic (n = 2). At 1 month (81 of 85) and 3 months (77 of 81) post-ligation, 95% of the patients had complete LAA closure by TEE. Of the patients undergoing 1-year TEE (n = 65), there was 98% complete LAA closure, including the patients with previous leaks. CONCLUSIONS LAA closure with the LARIAT device can be performed effectively with acceptably low access complications and periprocedural adverse events in this observational study.

Feasibility of closed-chest ligation of the left atrial appendage in humans

BACKGROUND Atrial fibrillation is associated with an increased risk of embolic events. The left atrial appendage (LAA) is believed to be an incubator for thrombus formation. LAA exclusion has been advocated to potentially reduce embolic events arising from the LAA. OBJECTIVE The aim of the study was to determine the feasibility of a closed-chest surgical suture ligation of the LAA in man. METHODS Thirteen patients undergoing either mitral valve surgery (n = 2) or electrophysiological study and radiofrequency catheter ablation for atrial fibrillation (n = 11) underwent ligation of the LAA with the LARIAT snare device. In patients having an ablation procedure, pericardial access was obtained prior to the patients undergoing radiofrequency catheter ablation. After transseptal catheterization, endocardial and epicaridal magnet-tipped guide wires were positioned under fluoroscopic guidance to stabilize the LAA. Transesophageal echocardiography (TEE) was used as guidance for positioning a marker balloon at the ostium of the LAA. An over-the-wire approach was used to guide the LARIAT snare device over the LAA to allow closure and suture ligation of the LAA. TEE and contrast fluoroscopy were used to confirm acute closure of the LAA. RESULTS Both mitral valve replacement (MVR) patients had complete closure of the LAA determined by visual inspection. Ten of 11 patients having ablation underwent a successful closed-chest LAA ligation procedure with TEE and contrast fluoroscopy verification of closure of the LAA. Only one of 11 procedures was terminated owing to the lack of echocardiography guidance of the snare over the marker balloon. One patient with pectus excavatum did have ligation of his LAA; however, a thorascopic procedure was required to remove the snare from the LAA owing to compression of the LARIAT by the concave sternum. There were no other significant complications. CONCLUSIONS Catheter-based surgical suture ligation of the LAA is feasible in humans. This novel catheter approach may be appropriate for patients with atrial fibrillation who are ineligible for anticoagulation therapy. Further investigation is needed to demonstrate the long-term safety and efficacy of LAA closure.

The effects of LAA ligation on LAA electrical activity.

BACKGROUND The arrhythmic role of the left atrial appendage (LAA) has been implicated in the maintenance of persistent atrial fibrillation. LAA isolation with catheter ablation has been successful but is limited by the risk of tamponade and electromechanical dissociation with the potential for LAA thrombus formation. OBJECTIVE To assess whether LAA ligation results in LAA electrical isolation. METHODS A total of 68 patients with contraindication or intolerance to oral anticoagulation therapy underwent LAA ligation with the LARIAT suture delivery device. Patients had unipolar [n = 30(44%)] or bipolar [n = 38(56%)] voltage measurements pre- and post-LAA ligation. RESULTS All 68 patients underwent successful LAA ligation. There was a statistically significant reduction in the mean LAA voltage from pre-ligation (unipolar pre-ligation voltage 1.1 ± 0.53 mV; bipolar pre-ligation voltage 4.7 ± 2.83 mV) to post-ligation (unipolar post-ligation voltage 0.3 ± 0.38 mV; bipolar post-ligation voltage 0.6 ± 0.27 mV). Ninety-four percent of the patients had a reduction in the LAA voltage after the closure of the snare, with 10 of 30 (33%) of the patients having complete elimination of LAA voltage with the initial tightening of the suture. Pacing from the LAA after the closure of the snare resulted in lack of capture of the left atrium in 28 of 31 patients. CONCLUSIONS The snare closure of the LAA using the LARIAT device produces an acute reduction in the LAA voltage and inhibits the capture of the left atrium during LAA pacing. Future studies are needed to determine whether LAA ligation affects atrial fibrillation burden.

Plasma ANP and Cyclic GMP Levels Versus Left Ventricular Performance at Different AV Delays in AV Sequential Pacing

Eleven resting patients with an implanted DDD pacemaker were studied. After 30 minutes of AV sequentiai pacing at a rate of 80 beats/min with three consecutive atrioventricular delays (AVDs; 100, 150, and 200 msec) peripheral venous blood was drawn for further analyses by specific radioimmunoassays of atrial natriuretic peptide (ANP) and the ANP second messenger, cyclic guanosine monophosphate (cGMP). Relative changes in left ventricular (LV) stroke volume following alterations of AVD were assessed by means of pulsed‐Doppler echocardiography through measurement of LV outflow time‐velocity integrals (TVI). The optimal AVD (oA VD) was defined in individual patients as that which was associated with the greatest TVI and with improvement over both other AVDs of more than 4%. The oA VD was found in nine patients. For these nine patients no significant differences in either plasma ANP or cGMP between various AVDs were observed. However, we found such differences with respect to values measured at oAVD; both ANP and cGMP levels were lowest at oAVD. Pooling together the data obtained in 11 patients at three AVDs, a positive correlation between ANP and cGMP levels was found (r = 0.7, P < 0.0001. n = 33). Moreover, changes of plasma ANP and cGMP induced by every A VD increment of 50 msec were also correlated (r = 0.6, P < 0.01, n = 22). It is concluded that in AV sequential pacing at rest piasma ANP reaches minimal levels at the AVD, which provides the best LV performance. Although levels of cGMP changed in parallel with those of ANP, low relative values of cGMP differences may limit the usefulness of cGMP assays in optimization of the AVD.

Depressed Systemic Arterial Compliance is Associated with the Severity of Heart Failure Symptoms in Moderate-to-Severe Aortic Stenosis: a Cross-Sectional Retrospective Study

Background: Patients with aortic stenosis (AS) may develop heart failure even in the absence of severe valve stenosis. Our aim was to assess the contribution of systemic arterial properties and the global left ventricular afterload to graded heart failure symptoms in AS. Methods: We retrospectively reviewed medical records of 157 consecutive subjects (mean age, 71±10 years; 79 women and 78 men) hospitalized owing to moderate-to-severe degenerative AS. Exclusion criteria included more than mild aortic insufficiency or disease of another valve, atrial fibrillation, coronary artery disease, severe respiratory disease or anemia. Heart failure symptoms were graded by NYHA class at admission. Systemic arterial compliance (SAC) and valvulo-arterial impedance (Zva) were derived from routine echocardiography and blood pressure. Results: Sixty-one patients were asymptomatic, 49 presented mild (NYHA II) and 47 moderate-to-severe (NYHA III-IV) heart failure symptoms. Mild symptoms were associated with lower SAC and transvalvular gradients, while more severe exercise intolerance coincided with older age, lower systolic blood pressure, smaller aortic valve area and depressed ejection fraction. By multiple ordinal logistic regression, the severity of heart failure symptoms was related to older age, depressed ejection fraction and lower SAC. Each decrease in SAC by 0.1 ml/m² per mmHg was associated with an increased adjusted odds ratio (OR) of a patient being in one higher category of heart failure symptoms graded as no symptoms, mild exercise intolerance and advanced exercise intolerance (OR: 1.16 [95% CI, 1.01-1.35], P=0.045). Conclusions: Depressed SAC may enhance exercise intolerance irrespective of stenosis severity or left ventricular systolic function in moderate-to-severe AS. This finding supports the importance of non-valvular factors for symptomatic status in AS.

Asymmetric Dimethylarginine versus Proton Pump Inhibitors Usage in Patients with Stable Coronary Artery Disease: A Cross-Sectional Study.

A recent experimental study suggested that proton pump inhibitors (PPI), widely used to prevent gastroduodenal complications of dual antiplatelet therapy, may increase the accumulation of the endogenous nitric oxide synthesis antagonist asymmetric dimethylarginine (ADMA), an adverse outcome predictor. Our aim was to assess the effect of PPI usage on circulating ADMA in coronary artery disease (CAD). Plasma ADMA levels were compared according to PPI use for ≥1 month prior to admission in 128 previously described non-diabetic men with stable CAD who were free of heart failure or other coexistent diseases. Patients on PPI tended to be older and with insignificantly lower estimated glomerular filtration rate (GFR). PPI use was not associated with any effect on plasma ADMA (0.51 ± 0.11 (SD) vs. 0.50 ± 0.10 µmol/L for those with PPI (n = 53) and without PPI (n = 75), respectively; p = 0.7). Additionally, plasma ADMA did not differ between PPI users and non-users stratified by a history of current smoking, CAD severity or extent. The adjustment for patients’ age and GFR did not substantially change the results. Thus, PPI usage does not appear to affect circulating ADMA in non-diabetic men with stable CAD. Whether novel mechanisms of adverse PPI effects on the vasculature can be translated into clinical conditions, requires further studies.

Implantable intravascular defibrillator: Defibrillation thresholds of an intravascular cardioverter-defibrillator compared with those of a conventional ICD in humans

BACKGROUND A percutaneous intravascular cardioverter-defibrillator (PICD) has been developed with a right ventricular (RV) single-coil lead and titanium electrodes in the superior vena cava (SVC)-brachiocephalic vein (BCV) region and the inferior vena cava (IVC). OBJECTIVE To compare defibrillation thresholds (DFTs) of the PICD with those of a conventional ICD in humans. METHODS Ten patients with ischemic cardiomyopathy and ejection fraction ≤35% were randomized to initial testing with either PICD or conventional ICD. A standard dual-coil lead was positioned in the RV apex. If randomized to PICD, the device was placed into the vasculature such that 1 titanium electrode was positioned in the SVC-BCV region and the second in the IVC. For PICD DFTs, the RV coil of the conventional ICD lead was connected to the PICD mandrel [shock vector: RV (+) to SVC-BCV (-) + IVC (-)]. When testing the conventional ICD, a subcutaneous pocket was formed in the left pectoralis region and the ICD was connected to the lead system and positioned in the pocket [shock vector: RV (+) to SVC (-) + active can (-)]. Each device was removed before testing with the other. A step-down binary search protocol determined the DFT, with the initial shock being 9 J. RESULTS The mean PICD DFT was 7.6 ± 3.3 J, and the conventional ICD system demonstrated a mean DFT of 9.5 ± 4.7 J (N = 10; paired t test, P = .28). CONCLUSION The intravascular defibrillator has DFTs similar to those of commercially available ICDs.

Chronic implantation of intravascular cardioverter defibrillator in a canine model: device stability, vascular patency, and anchor histology.

A percutaneously placed implantable intravascular defibrillator (PICD) has been developed with a right ventricular (RV) single‐coil lead and titanium electrodes in the superior vena cava (SVC) and the inferior vena cava (IVC). This study evaluated implant techniques, device stability, and anchor histology of the PICD over 9 months in a canine model.

Management of Patients with Atrial Fibrillation: Focus on Treatment Options

Atrial fibrillation (AF) is leading cardiac arrhythmia with important clinical implications. Its diagnosis is usually made on the basis on 12-lead ECG or 24-hour Holter monitoring. More and more clinical evidence supports diagnostic use of cardiac event recorders and cardiovascular implantable electronic devices (CIED). Treatment options in patients with atrial fibrillation are extensive and are based on chosen rhythm and/or rate control strategy. The use and selected contraindications to AF related pharmacotherapy, including anticoagulants are shown. Nonpharmacological treatments, comorbidities and risk factors control remain mainstay in the treatment of patients with AF. Electrical cardioversion consists important choice in rhythm control strategy. Much progress has been made in the field of catheter ablation and cardiac surgery methods. Left atrial appendage occlusion/closure may be beneficial in patients with AF. CIED are used with clinical benefits in both, rhythm and rate control. Pacemakers, implantable cardioverter-defibrillators and cardiac resynchronization therapy devices with different pacing modes have guaranteed place in the treatment of patients with AF. On the other hand, the concepts of permanent leadless cardiac pacing, atrial dyssynchrony syndrome treatment and His-bundle or para-Hisian pacing have been proposed. This review summarizes and discusses current and novel treatment options in patients with atrial fibrillation.

Rytm z szerokimi zespołami QRS — trudności diagnostyczne

In the case described we demonstrate the difficulty in interpreting the rhythm with wide QRS complex. The 25 year old patient with ventricular pre-excitation and periodically occurring rhythm with wide QRS complex, morphology meets the electrocardiographic (ECG) criteria for ventricular arrhythmias and in the absence of P waves. Initial difficulties in the interpretation of ECG were explained by electrophysiological study in which we demonstrate the supraventricular origin of rhythm conducted to the ventricles with pre-excitation. Radio frequency ablation of the accessory pathway reveals the periodically occurring low-atrial rhythm originating in the muscle of the coronary sinus. Very close proximity of the atrial rhythm and the accessory pathway resulted instant conduction of impulse to the ventricle and cause perfect imitation of ventricular rhythm. This case draws attention on the need to take account of none-sinus rhythm with ventricular preexcitation during diagnosis of rhythm with wide QRS complex.