Nauman Ahmed

Clinical Predictors of Pacemaker Implantation in Patients with Syncope Receiving Implantable Loop Recorder with or without ECG Conduction Abnormalities.

Implantable loop recorders (ILR) allow prolonged cardiac rhythm monitoring and improved diagnostic yield in syncope patients. Predictive factors for pacemaker (PM) implantation in the ILR population with unexplained syncope have not been adequately investigated. In this single center, retrospective, observational study we investigated factors that predict PM implantation in this population.

Implantable Cardioverter Defibrillators in Octogenarians: Clinical Outcomes From a Single Center

Aims Limited data exist on outcomes in very elderly ICD recipients. We describe outcomes in new ICD and Cardiac Resynchronisation Therapy with Defibrillator (CRT-D) implants in octogenarians at our institution. Methods Patients aged 80 years and above who underwent de novo ICD or CRT-D implantation from January 2006 to July 2012 were identified. Clinical data were collected from the procedural record, medical and ICD notes. Baseline characteristics were compared using independent sample t test for continuous variables and Fisher’s exact test for categorical variables. Kaplan-Meier curves were constructed. Results Ten per cent of all new ICD/CRT-D implants were aged 80 years and over. Median age was 83.0 years. Median follow-up was 29 months. Death occurred in 17 (34%). Median time to death was 23 months. Three deaths (6%) occurred within 12 months of ICD implantation. Appropriate therapy (ATP or shock) occurred in 19 (38%). Inappropriate therapy occurred in 6 (12%). Rates of appropriate shocks and inappropriate therapy (shocks and ATP) and significant valvular incompetence were higher amongst deceased patients (P=0.03 OR 5.9 95% CI 1.3-27) and (P=0.02 OR 12 95% CI 1.3-112). Univariate analysis identified diuretic use (P=0.008 95% C.I. 0.05 to 0.63) and appropriate shock (P= 0.025 95% C.I. 1.25 to 26.3) as predictors of mortality. Conclusion Octogenarians make up a small but increasing number of ICD recipients. This study highlights high survival rates at one year with acceptable rates of appropriate and inappropriate device therapy. Ongoing debate regarding the appropriateness of ICD in very elderly patients is warranted.

Premature ventricular beats initiate recurrent ventricular fibrillation in early repolarization syndrome

An early repolarization (ER) pattern on electrocardiography was historically considered a benign finding; however, this finding in the inferior and lateral leads has recently been associated with idiopathic ventricular fibrillation (VF). Here we describe a case of a 29‐year‐old man with an ER pattern, who experienced recurrent implantable cardioverter‐defibrillator (ICD) shocks for ventricular tachycardia (VT) and VF. An ICD interrogation demonstrated how VF and VT were repeatedly initiated by closely coupled premature ventricular beats.

Improved diagnostic role of CMR in acute coronary syndromes and unobstructed coronary arteries: the importance of time-to-CMR

Background Acute coronary syndrome (ACS) still remains one of the leading causes of mortality and morbidity. In the literature 7-15% of patients with ACS have non obstructive coronary artery disease. In these patients CMR can identify different underlying etiologies, mainly myocarditis, myocardial infarction (MI) with spontaneous recanalization/embolus or Tako-Tsubo cardiomyopathy. However the diagnostic pick-up rate of these aetiologies by CMR is highly variable in the literature and patients are not consistently scanned in the same time window.

134 Incremental Value of Cardiovascular Magnetic Resonance Imaging in Patients Surviving non Traumatic out of Hospital Cardiac Arrest: A Tertiary UK Centre Experience

Background Non-traumatic out of hospital cardiac arrest (OOHCA) is one of the leading causes of death in western world. Acute coronary syndrome (ACS) is the most common aetiology of OOHCA with a culprit artery lesion identified on invasive angiography. However, 1/3rd of patients with OOHCA have unobstructed coronaries on angiography. Non-invasive tissue characterisation by cardiovascular magnetic resonance (CMR) has the potential to establish the final diagnosis in patients with OOHCA with obstructed coronaries as well as with unobstructed coronary arteries. Methods We retrospectively reviewed the database in our tertiary cardiothoracic centre from October 2009 to November 2013. We identified 54 consecutive patients who were referred for a CMR following an OOHCA. A comprehensive CMR protocol with cine, oedema and scar imaging was used. All scans were done within 6–8 weeks of the index event and was reported by a consultant with >10years of experience in CMR. Results Out of the 54 patients (16 female, age range 21–84 years), 29 (54%) had coronary artery disease, in which the culprit was treated by primary angioplasty and 25 (46%) patients had unobstructed coronaries. Of the latter, 3 had hypertrophic cardiomyopathy, 4 had myocarditis or cardiac sarcoid, 2 had non-ischaemic dilated cardiomyopathy, 2 had LV non-compaction (LVNC) cardiomyopathy, 7 had nonspecific abnormalities and 9 had completely normal CMR scan. In all patients (n = 29) with significant CAD on angiography CMR identified a myocardial infarction (100%). So in total, 40/54 (74%) of OOHCA, a cause was found on CMR. In 11/25 (44%) of OOHCA with unobstructed coronaries a diagnosis was made whereas in 9/25 (36%), a normal CMR was suggestive of a primary arrhythmic cause, thereby guiding further therapy (ICD). Conclusions In adults surviving a non-traumatic OOHCA with unobstructed coronaries on angiogram, CMR could identify the underlying aetiology in the large majority of cases. This has potential implications for treatment and prognosis.

Incremental diagnostic role of cardiac MRI in young-middle aged patients with high-grade atrio-ventricular block

Background Atrio-ventricular (AV) block is a common bradyarrhythmia in the elderly, but is a rare event in young or middle-aged adults, often leading to pacemaker implantation without further investigation, though underlying aetiology influences both treatment strategies and prognosis. Cardiovascular magnetic resonance (CMR) has the potential to identify an underlying aetiology for AV block, over and above transthoracic echocardiogram (TTE), which is offered as the first imaging technique. We sought to assess the diagnostic additive role of CMR in young and middle aged adults (18-60 years) with high-grade AV block and to determine which findings on CMR best predict clinical impact.

Successful transvenous cardiac resynchronisation therapy in a case of coronary sinus ostial atresia

A 42-year-old male with non-ischaemic dilated cardiomyopathy, sinus rhythm, LBBB morphology (QRS duration 150ms), New York Heart Association class III heart failure symptoms and recurrent syncope with non-sustained ventricular tachycardia was referred for cardiac resynchronisation therapy with defibrillator (CRT-D) implantation. Implantation of the LV lead proved difficult due to inability to cannulate the coronary sinus (CS) …

T2 values of the acutely infarcted myocardium following primary PCI: the relationship with infarct characteristics and gadolinium extracellular volume of distribution.

Background T2 mapping has been shown to detect myocardial oedema as assessed by histology in animals, and is a promising sequence to detect the area at risk in STEMI. The specific cut off value to identify abnormal myocardium in STEMI has not been identified nor have the effects of infarct characteristics on T2 valves. The extra cellular volume fraction (ECV) has been validated against histology in humans. The aims of this study were to identify a cut-off T2 for prediction of myocardial oedema following acute reperfused myocardial infarction and determine if infarct characteristics affect T2 values. In addition, this study aims to determine if T2 values are associated with the ECV following STEMI. Methods 50 consecutive patients presenting with STEMI to the Bristol Heart Institute Primary PCI service were approached for inclusion in the study. Patients had a CMR scan day 2 following STEMI. T2 values were assessed by T2 mapping. The myocardium was divided according to the AHA segments. Regional wall motion, LGE transmurality, presence of persistent microvascular obstruction (PMVO) and T2 values were assessed per segment. Segments were deemed affected if they did not have normal wall motion. In addition, a further 30 patients had a CMR day 2 following STEMI. Pre-contrast T1, T2 valves were assessed. Post contrast T1 was measured at 25 minutes following contrast administration. ECV was calculated as:

Cardiovascular magnetic resonance imaging in patients with MR-conditional devices: a UK tertiary centre experience on image quality and change in patients management

Background Cardiovascular magnetic resonance (CMR) examinations is increasingly used in daily clinical practice. Conventional pacemakers and implantable cardioverter-defibrillators (ICD) have always been regarded as a contraindication to MR imaging. However the introduction of MR-conditional systems have significantly improved access to MR examinations. Limited data exists regarding indications and management outcomes and impact of different cardiac rhythm devices on image quality

Safety, tolerability and feasibility of adenosine stress CMR in high-risk patients

Background Adenosine stress cardiovascular magnetic resonance (CMR) provides effective cardiac prognostication in patients with suspected coronary artery disease. However its use has been limited in high-risk patients and some reservations exist about offering adenosine stress CMR in patients with significant aortic stenosis, asthma, severe left ventricular (LV) systolic dysfunction, significant left main stem (LMS) disease and age >80years.