title: Adverse response to cardiac resynchronisation therapy in patients with septal scar on cardiac MRI preventing a septal right ventricular lead position.
abstract: OBJECTIVE
  Myocardial scar is an adverse factor when considering which patients are likely to respond to cardiac resynchronisation therapy (CRT). We hypothesized that septal scarring on magnetic resonance imaging (MRI) may be associated with a poor outcome from CRT, which may relate to the inability to place the right ventricular (RV) lead in the septum.
  
  
  METHODS
  Fifty patients (ejection fractions, 25 ± 8%; 45 men, 62.8 ± 14 years; 26 dilated cardiomyopathy; and 24 ischaemic cardiomyopathy (ICM)) receiving CRT underwent delayed enhancement cardiac MRI to assess location and burden of myocardial scar. Acute hemodynamic response (AHR) was evaluated at implant with a pressure wire in the left ventricular (LV) cavity. LV remodelling was determined by reduction in LV end-systolic volume at 6 months.
  
  
  RESULTS
  The presence of ICM with septal scar was associated with a poor acute and chronic response to CRT. This was predominantly due to a worse response in patients with septal scar. Patients without septal scar had a better AHR with a 26.7 ± 28.9% rise in LV dP/dt (max) from baseline vs. -2.8 ± 14.5% for patients with septal scar (P = 0.01) with Biventricular (BIV) pacing. A greater proportion remodelled (56% vs. 20% (P = 0.02)). Furthermore, only 33% of patients with septal scar had an RV septal lead compared with 66% with no septal scar (P = 0.03).
  
  
  CONCLUSIONS
  The presence of septal scar was associated with a poor acute and chronic response to CRT. This may relate to the inability to achieve a RV septal lead placement.
authors: Department of Imaging Sciences, The Rayne Institute, Kings College London, London, Great Britain, UK. simon.duckett@kcl.ac.uk
authors: Simon G
authors: SG
authors: Duckett
authors: Matthew
authors: M
authors: Ginks
authors: Anoop
authors: A
authors: Shetty
authors: Senthil
authors: S
authors: Kirubakaran
authors: Julian
authors: J
authors: Bostock
authors: Stam
authors: S
authors: Kapetanakis
authors: Jaswinder
authors: J
authors: Gill
authors: Gerry
authors: G
authors: Carr-White
authors: Reza
authors: R
authors: Razavi
authors: C Aldo
authors: CA
authors: Rinaldi
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects* / Q000379:methods; D002311:Cardiomyopathy, Dilated / Q000473:pathology / Q000628:therapy; D002921:Cicatrix / Q000473:pathology* / Q000628:therapy; D015331:Cohort Studies; D016001:Confidence Intervals; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D006346:Heart Septum / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D016017:Odds Ratio; D012189:Retrospective Studies; D018570:Risk Assessment; D013318:Stroke Volume; D016896:Treatment Outcome; D020257:Ventricular Remodeling / Q000502:physiology*