Thread by @JACCJournals

New #Coronavirus Research For #EPeeps (1/10):
While the use of hydroxychloroquine and azithromycin in patients with #COVID19 remains controversial, many patients receive this therapy. The primary adverse effect is QT prolongation and torsades de pointes/polymorphic VT. #JACCCEP

(2/10): A topical #COVID19 research letter published in #JACCCEP from investigators at @HeartsInRhythm in Vancouver explore the use of a handheld #ECG device versus a standard 12-lead ECG for QT monitoring. bit.ly/34joL10

(3/10) The handheld #ECG would be ideal because it could minimize healthcare worker exposure. The study cohort included 22 patients referred to their center for a possible inherited arrhythmia syndrome. bit.ly/34joL10 #JACCCEP

(4/10) After a standard #ECG, participants then recorded single-lead ECGs in Lead 1, Lead II and precordial lead position of V1-V2. Blinded assessment of the QT interval using the maximum slope technique was the primary endpoint (Correction via Bazett’s formula). #JACCCEP

(5/10) After excluding two patients for inability to reliably measure the QT, the authors made the following two major observations:

(6/10) 1⃣-There was no difference in the max QTc interval measured by 12-lead ECG compared to the max QTc interval measured across all positions using the handheld device (401 vs. 404ms, p=0.259)

(7/10) 2⃣-QTc measured by 12-lead ECG was significantly longer than the lead I QTc (+23ms, 95% CI 13-34, p<0.001), and the precordial lead QTc on the handheld device (+11ms, 95% CI 1-20, p=0.018). bit.ly/34joL10 #JACCCEP

(8/10) They concluded: QTC intervals can be reproducibly measured w/ a single-lead handheld device, but it requires capture of multiple vectors. Importantly: the maximal QTc by 12 lead was consistently *longer* than the QTc measured in a single lead position alone. #JACCCEP

(9/10) Clinical Implications: While it is appealing to use handheld #ECG for #COVID19 patients in context of off-label indications for QT-prolonging drugs, handheld devices should be used in multiple lead positions—including precordial positions. bit.ly/34joL10 #JACCCEP

(10/10) The authors further add that measuring change in QTc (delta) may augment risk stratification in hospitalized patients, but is not sufficient as both the absolute QTc and delta QTc informs the risk of pro-arrythmia. #JACCCEP

Download & read today: bit.ly/34joL10