Definition: Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
Input: Context: Non-response to cardiac resynchronization therapy (CRT) might be due to insufficient resynchronization as a result of a sub-optimal left ventricular lead positon (LV-LP).', 'To evaluate the impact of different LV-LPs on mortality and symptomatic improvement in a large cohort of patients treated with CRT.', "We performed a nationwide cohort study on consecutive patients receiving a CRT device from 1997 to 2012 registered in the Danish pacemaker and ICD register. The LV-LP was defined clockwise in a left anterior oblique (LAO) view and categorized as anterior (2 o'clock), lateral (2 to 4 o'clock) or posterior (>4 o'clock), and as basal, mid-ventricular, or apical in a right anterior oblique (RAO) view. Outcomes were all cause mortality and clinical response (improvement in NYHA class). Adjusted hazard ratio (aHR) and odds ratio (aOR) with 95% confidence intervals (CI) were calculated using Cox and logistic regression analysis.", 'A total of 2594 patients were included. A lateral LV-LP, (aHR 0.77, 95% CI 0.64-0.92, p=0.004), and a posterior LV-LP, (aHR 0.71 95% CI 0.53-0.97, p=0.029) were associated with lower mortality as compared to an anterior LV-LP. A lateral LV-PV was associated with higher clinical response rate as compared to an anterior LV-LP (aOR 1.37, 1.03-1.83, p=0.032). No statistically significant associations were observed between LV-LP in the RAO view and mortality or clinical response.
Answer: An anterior left ventricular lead position is associated with increased all-cause mortality and lower clinical response rate in patients treated with CRT and should be avoided.
Output:
Is an anterior left ventricular lead position associated with increased mortality and non-response in cardiac resynchronization therapy?