Prevalence of prolonged corrected QT interval and its impact on outcomes in patients admitted in medical intensive care unit

Pandharinath S. Gawali, Sachin N. Solanke, Sudhir L. Tungikar


Background: The long QT syndrome (LQTS) is a disorder of myocardial repolarization characterized by a prolonged QT interval on the electrocardiogram (ECG). Hence the present study was aimed to determine prevalence of QT prolongation of the ECG and to assess its impact on outcomes in patients admitted in medical ICU of Noor Hospital of IIMSR Medical College, Badnapur, Jalna, Maharashtra, India.

Methods: This prospective observational study was carried out during the period of October 2016 to March 2018, for assessment of prevalence of prolonged QTc at admission and its impact on outcomes in medical ICU. QTc calculated by bazett’s formula of >440 ms for males and >460 ms for females was considered as prolonged. Details of illness, clinical observations and laboratory parameters were also monitored.

Results: The total 150 patients were studied and there was a high prevalence (32%) of prolonged QTc at admission to the ICU which reduced to 20.5% on day 3. Patients with prolonged QTc were found to be at high risk for adverse outcomes and their ICU and hospital stay was more.

Conclusions: The study concluded that prolonged QTc is common in authors’ medical ICU at admission (32%). Patients with QTc prolongation were at higher risk for adverse outcomes and their ICU and hospital stay was more.


Corrected QT interval, Intensive Care Unit (ICU), Prevalence

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