S. Paraskevaidis

Novel non-invasive P wave analysis for the prediction of paroxysmal atrial fibrillation recurrences in patients without structural heart disease: A prospective pilot study

OBJECTIVES The pathogenetic mechanisms responsible for the initiation and recurrence of PAF are not fully elucidated and vary among individuals. We evaluated the ability of a novel non-invasive approach based on P wave wavelet analysis to predict symptomatic paroxysmal atrial fibrillation (PAF) recurrences in individuals without structural heart disease. METHODS We studied 50 patients (24 males, mean age 54.9 ± 9.8 years) presented to our emergency department with a symptomatic episode of PAF. The patients were followed-up for 12.1 ± 0.1 months and classified into two groups according to the number of PAF episodes: Group A (<5 PAF, n = 33), Group B (≥ 5 PAF, n = 17). A third Group of 50 healthy individuals without history of PAF was used as control. Study groups underwent echocardiography and orthogonal ECG-based wavelet analyses of P waves at baseline and follow-up. Maximum and mean P wave energies were calculated in each subject at each orthogonal lead using the Morlet wavelet analysis. RESULTS Larger P wave energies at X lead and relatively larger left atrium were independently associated with >5 PAF episodes vs. <5 PAF episodes. No difference in P wave duration was detected between Groups A and B (p > 0.1), whereas Group A and B patients had longer P waves at Z lead compared to Group C (86.4 ± 13 vs. 71.5 ± 15 msec, p < 0.001). CONCLUSIONS P wave wavelet analysis can reliably predict the generation and recurrence of PAF within a year. P wave wavelet analysis could contribute to the early identification of patients at risk for increased number of PAF recurrences.

Coronary–subclavian steal syndrome: treatment with percutaneous transluminal angioplasty and stent placement

Abstract. The aim of this study was to assess the efficacy of percutaneous transluminal angioplasty (PTA) and stenting in the management of the coronary-subclavian steal syndrome (CSSS). A 56-year-old man presented with CSSS due to occlusion of the left subclavian artery. He was treated with PTA and placement of two stents in the left subclavian artery. Systolic blood pressure became equal in both arms and dizziness disappeared. There were no complications. Percutaneous transluminal angioplasty and stenting can effectively and safely manage CSSS.

Patients with hypertrophic cardiomyopathy at risk for paroxysmal atrial fibrillation: advanced echocardiographic evaluation of the left atrium combined with non-invasive P-wave analysis

AIMS The maintenance of sinus rhythm is crucial for the functional capacity of patients with hypertrophic cardiomyopathy (HCM). Using a multimodality approach, we attempted to identify potential predictors of paroxysmal atrial fibrillation (PAF) in HCM patients. METHODS AND RESULTS Thirty HCM patients (17 males, mean age 57.9 ± 13.6) with at least one documented PAF episode and 32 age- and sex-matched HCM control patients as well as 25 healthy volunteers were studied in sinus rhythm. Study subjects underwent 2D echocardiography including a colour Doppler myocardial imaging evaluation of the left atrium (LA). Additionally, an orthogonal electrocardiogram was acquired; P-wave duration, maximum, and mean energies were calculated for each subject at each orthogonal lead and the composite vector axis using the Morlet wavelet analysis. Compared with HCM controls, in HCM-PAF patients, LA antero-posterior diameter was significantly enlarged (LADAP: 46.1 ± 5.9 vs. 40.0 ± 4.7 mm, P < 0.001), peak strain rate of the LA lateral wall in the reservoir phase was significantly decreased (LAT peak SR-S: 1.93 ± 0.51 vs. 2.55 ± 0.83 s(-1), P < 0.01), and P-wave duration in the Z-lead was significantly prolonged (P-durZ: 106.9 ± 24.6 vs. 86.2 ± 14.3 ms, P < 0.001). Cut-off values and areas under the curve (AUCs) for individual parameters were 42.0 mm, 2.32 s(-1), and 98.8 ms and 0.81, 0.74, and 0.78, respectively. A multivariable model combining LADAP, LAT peak SR-S and P-durZ had an AUC of 0.90, a sensitivity of 0.87, and a specificity of 0.91 for identifying PAF patients. CONCLUSION P-wave duration combined with LA antero-posterior diameter and myocardial deformation indices resulted in a higher power for discriminating HCM-PAF patients, when compared with individual parameters derived from either wavelet analysis or 2D echocardiography.

Hypertrophic cardiomyopathy with midventricular obstruction and apical aneurysm formation in a single family: case report

BackgroundHypertrophic cardiomyopathy (HCM) is an extremely heterogeneous disease. An under recognized and very often missed subgroup within this broad spectrum concerns patients with left ventricular (LV) apical aneurysms in the absence of coronary artery disease.Case presentationWe describe a case of HCM with midventricular obstruction and apical aneurysm formation in 3 patients coming from a single family. This HCM pattern was detected by 2D-echocardiography and confirmed by cardiac magnetic resonance imaging. A cardioverter defibrillator was implanted in one of the patients because of non-sustained ventricular tachycardia detected in 24-h Holter monitoring and an abrupt drop in systolic blood pressure during maximal exercise test. The defibrillator activated 8 months after implantation by suppression of a ventricular tachycardia providing anti-tachycardia pacing. The patient died due to refractory heart failure 2 years after initial evaluation. The rest of the patients are stable after a 2.5-y follow-up period.ConclusionThe detection of apical aneurysm by echocardiography in HCM patients may be complicated. Ventricular tachycardia arising from the scarred aneurysm wall may often occur predisposing to sudden death.

Implantable cardioverter defibrillators for primary prevention of sudden death in hypertrophic cardiomyopathy.

Aims Sudden cardiac death (SCD) may complicate hypertrophic cardiomyopathy (HCM) natural course. Patient selection for implantable cardioverter defibrillator (ICD) therapy in the primary prevention setting is still a challenge. Methods Thirty-seven HCM patients with a primary prevention ICD were included. All patients underwent preimplantation SCD risk assessment and semi-annual device interrogation during follow-up. Primary end point was the time to first appropriate ICD intervention including antitachycardia pacing or shock. Inappropriately delivered ICD therapies served as secondary end point. Results During a median follow-up of 3.1 years, 10 (27%) patients received one or more appropriate ICD therapies. First appropriate ICD intervention rate was 7.2%/year (95% CI: 3.4–13.2) with a 5-year cumulative probability of 29.2 ± 7.4%. No SCD risk marker was significantly associated with the primary end point, whereas event rates were comparable among patients with one, two or three or more SCD risk markers (log-rank P = 0.58). Patients with a history of SCD in first-degree relatives with HCM were at 3.8 times higher risk of experiencing an ICD intervention compared with those with no family history of SCD (HR: 3.8; 95% CI: 1.0–14.1, P = 0.05). Seven (18.9%) patients experienced one or more inappropriate ICD therapies; beta-blocker therapy was associated with 75% fewer inappropriate ICD interventions (HR: 0.15; 95% CI: 0.03–0.89). Conclusion Current criteria identify a subgroup of patients with HCM at increased risk of major arrhythmic events as indicated by high ICD intervention rates. However, no individual risk marker demonstrated superior predictive ability over the others, whereas simple arithmetic summing of risk markers was not associated with increased ICD intervention rates.

P wave analysis with wavelets identifies hypertensive patients at risk of recurrence of atrial fibrillation: A case-control study and 1 year follow-up

AIMS Hypertension is a major risk factor for atrial fibrillation (AF); however, reliable non-invasive tools to assess AF risk in hypertensive patients are lacking. We sought to evaluate the efficacy of P wave wavelet analysis in predicting AF risk recurrence in a hypertensive cohort. METHODS We studied 37 hypertensive patients who presented with an AF episode for the first time and 37 age- and sex-matched hypertensive controls without AF. P wave duration and energy variables were measured for each subject [i.e. mean and max P wave energy along horizontal (x), coronal (y) and sagittal (z) axes in low, intermediate and high frequency bands]. AF-free survival was assessed over a follow-up of 12.1±0.4months. RESULTS P wave duration (Pdurz) and mean P wave energy in the intermediate frequency band across sagittal axis (mean2z) were independently associated with baseline AF status (p=0.008 and p=0.001, respectively). Based on optimal cut-off points, four groups were formed: Pdurz<83.2ms/mean2z<6.2μV(2) (n=23), Pdurz<83.2ms/mean2z≥6.2μV(2) (n=10), Pdurz≥83.2ms/mean2z<6.2μV(2) (n=22) and Pdurz≥83.2ms/mean2z≥6.2μV(2) (n=19). AF-free survival decreased (Log Rank p<0.0001) from low risk (Pdurz<83.2ms/mean2z<6.2μV(2)) to high-risk group (Pdurz≥83.2ms/mean2z≥6.2μV(2)). Patients presenting with longer and higher energy P waves were at 18 times higher AF risk compared to those with neither (OR: 17.6, 95% CI: 3.7-84.3) even after adjustment for age, sex, hypertension duration, left atrial size, beta-blocker, ACEi/ARBs and statin therapy. CONCLUSIONS P wave temporal and energy characteristics extracted using wavelet analysis can potentially serve as screening tool to identify hypertensive patients at risk of AF recurrence.

Wavelet-based analysis of P waves identifies patients with lone atrial fibrillation: A cross-sectional pilot study

atrial fibrillation: A cross-sectional pilot study George Dakos ⁎⁎, Yiannis S. Chatzizisis ⁎, Dimitrios Konstantinou , Ioanna Chouvarda , Dimitrios Filos , Stylianos Paraskevaidis , Lilian Mantziari , Nicos Maglaveras , Haralambos Karvounis , Ioannis Styliadis , Vassilios Vassilikos a,e a First Department of Cardiology, AHEPA University Hospital, Aristotle University Medical School, Thessaloniki, Greece b Cardiovascular Division, Brigham and Womens Hospital, Harvard Medical School, Boston, MA, USA c Laboratory of Medical Informatics, Aristotle University Medical School, Thessaloniki, Greece d Department of Cardiology, Electrophysiology Unit, Royal Brompton Hospital, London, UK e Third Department of Cardiology, Hippokrateion University Hospital, Aristotle University Medical School, Thessaloniki, Greece

Percutaneous Extraction of Transvenous Permanent Pacemaker/Defibrillator Leads

Background. Widespread use of cardiovascular implantable electronic devices has inevitably increased the need for lead revision/replacement. We report our experience in percutaneous extraction of transvenous permanent pacemaker/defibrillator leads. Methods. Thirty-six patients admitted to our centre from September 2005 through October 2012 for percutaneous lead extraction were included. Lead removal was attempted using Spectranetics traction-type system (Spectranetics Corp., Colorado, CO, USA) and VascoExtor countertraction-type system (Vascomed GmbH, Weil am Rhein, Germany). Results. Lead extraction was attempted in 59 leads from 36 patients (27 men), mean ± SD age 61 ± 5 years, with permanent pacemaker (n = 25), defibrillator (n = 8), or cardiac resynchronisation therapy (n = 3) with a mean ± SD implant duration of 50 ± 23 months. The indications for lead removal included pocket infection (n = 23), endocarditis (n = 2), and ventricular (n = 10) and atrial lead dysfunction (n = 1). Traction device was used for 33 leads and countertraction device for 26 leads. Mean ± SD fluoroscopy time was 4 ± 2 minutes/lead for leads implanted <48 months (n = 38) and 7 ± 3 minutes/lead for leads implanted >48 months (n = 21), P = 0.03. Complete procedural success rate was 91.7% and clinical procedural success rate was 100%, while lead procedural success rate was 95%. Conclusions. In conclusion, percutaneous extraction of transvenous permanent pacemaker/defibrillator leads using dedicated removal tools is both feasible and safe.