JOURNAL ARTICLE

Among patients with left bundle branch block, T-wave peak to T-wave end time is prolonged in the presence of acute coronary occlusion

Kenneth W Dodd, Kendra D Elm, Erin M Dodd, Stephen W Smith
International Journal of Cardiology 2017 June 1, 236: 1-4
28082087

BACKGROUND: Assessing the effect of myocardial ischemia on ventricular repolarization in the setting of left bundle branch block (LBBB) poses a challenge due to secondary prolongation of the QT interval inherent in LBBB. The T-wave peak to T-wave end (TpTe) interval has been noted to prolong during myocardial ischemia and correct after reperfusion in patients with normal conduction. Here we compare the TpTe intervals of patients with LBBB both with and without complete acute coronary occlusion (ACO).

METHODS: Retrospectively, emergency department patients with LBBB and symptoms of myocardial ischemia were identified both with angiographically-proven ACO and with No-ACO. The longest QT, JT, and TpTe intervals were analyzed.

RESULTS: The ACO and No-ACO groups consisted of 33 and 129 patients, respectively. The mean TpTe was longer in ACO (103.6ms [95%CI 98.5-108.7]) compared to No-ACO patients (88.6ms [95%CI 85.3-91.9]) (P<0.0001) and this held true after correction for heart rate. In ACO versus No-ACO, the TpTe also more frequently exceeded prolongation cutoffs of 85ms (30 [90%] versus 69 [54%]) and 100ms (25 [76%] versus 42 [33%]) (P<0.0001 for all). The mean QT, JT, QTc, and JTc intervals were not significantly different between the groups for either the Bazett's or Rautaharju's correction formulas.

CONCLUSIONS: In patients with LBBB on the ECG, the TpTe is longer and more frequently prolonged in patients with ACO compared to patients without ACO. Future studies of ventricular repolarization in patients with LBBB should include analyses of the TpTe interval.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
28082087
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"