br Discussion The implant of
Discussion The implant of a CRT device in a patient with a resting ejection fraction of 50% represents off-guideline use of this therapy . However, since the patient׳s significant NYHA Class III symptoms, LBBB and exertional ventricular dysfunction achieved evidence-based levels for improvement with cardiac resynchronization, a decision was made to offer the treatment to the patient. Indeed, the guidelines do not explicitly state that the ejection fraction should be evaluated only at rest and this patient did meet the official rgd peptide guideline criteria if we use the exercise echo data instead of the resting echo data. This is especially relevant as her symptoms correlated with the echocardiographic findings. Pathophysiologically we hypothesize that the chronotropic response not only stressed her hemodynamic aspects of cardiac function but caused further conduction delays that led to left ventricular dysfunction, functional mitral regurgitation and hemodynamic deterioration. To date, there has been one other case report of a CRT implantation in a patient with a normal EF at rest but with an inter-ventricular conduction delay (IVCD) in a LBBB pattern, an elevated pulmonary capillary wedge pressure on invasive hemodynamic monitoring and left ventricular dyssynchrony measured by pressure–volume loop-derived analysis . In this case, the patient displayed NYHA Class III symptoms that improved considerably after implant. Implantation of CRT outside of guidance-based indications is not unique to clinical practice in the United States. A 2010 evaluation of US usage of CRT found that almost a quarter of all CRT devices were placed for off-society-guideline and off-FDA labeled indications, including patients with NYHA Class I and II symptoms, QRS duration <120ms and EF greater than 35% (13%, 12% and 1.3% of the cohort respectively) . Although at the outset, the data may seem to represent inappropriate practice patterns, the indications for CRT are continually expanding and the most recent guidelines for device-based therapy now include CRT for those with less severe heart failure symptoms [section deleted] . Although still under evaluation, there is increasing evidence that at least three additional groups might benefit from CRT: (1) CRT for heart failure and preserved EF, (2) CRT to correct mitral regurgitation and (3) CRT for patients with complete heart block and preserved left ventricular function. On the other hand, while until very recently there had been mixed evidence for CRT for heart failure and a narrow QRS, [4–6] the findings of the EchoCRT trial  strongly suggest that patients with a QRS duration of <130ms do not benefit from forced biventricular pacing even if they have evidence of left ventricular dyssynchrony.
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Introduction Lead perforation is a rare complication of device implantation with an incidence varying between 0.3% and 1.2% [1–3]. It usually occurs within the first 24h after implantation, more often with active fixation leads and in the atrial aspect . Delayed lead perforations, those diagnosed later than one month after implantation, are very rare . Previous use of temporary pacing wire seems to increase the risk of ventricular perforation . The incidence of perforation has been on the decline as the leads have become more flexible, less stiff and thinner .
Case report A 69-year-old Caucasian woman presented with a history of syncope and was found to have complete atrio-ventricular block (Fig. 1a). A dual-chamber permanent pacemaker (Ensura MRI SureScan EN1DR01, Medtronic Inc., Minneapolis, MN, USA) implantation was performed. A 7-French passive fixation lead (Medtronic 5554 – 53cm passive fixation lead, Silicone) was inserted via the left cephalic vein approach and positioned in the right atrial (RA) appendage and the right ventricular lead (Medtronic 5054 – 53cm passive fixation lead, Silicone) was implanted in the apical septum without any immediate complication.