Morocho-Saldarriaga et al. (2026)
Abstract
Background: Torsades de pointes (TdP) is a polymorphic ventricular tachycardia associated with
QT prolongation and may deteriorate into ventricular fibrillation. Hypokalemia and
hypomagnesemia reduce repolarization reserve and frequently coexist with QT-prolonging drugs,
gastrointestinal losses, or renal electrolyte-wasting mechanisms. Objective: To synthesize clinical
presentation, nephrologic and pharmacologic triggers, electrocardiographic diagnosis, and
emergency management strategies reported in case reports and series of TdP associated with
hypokalemia and/or hypomagnesemia. Methods: Narrative systematic review conducted
according to PRISMA 2020 principles. PubMed/MEDLINE was searched from inception through
August 31, 2026, complemented by reference tracking. The primary strategy combined terms for
TdP, hypokalemia, hypomagnesemia, and case reports. Cases were eligible when TdP was
documented and clinically relevant K+ and/or Mg2+ abnormalities were reported. Reporting
quality was appraised using JBI case-report/case-series domains. Results: The focused search
retrieved 43 records. Fifteen single-patient reports were retained for structured synthesis.
Reference tracking additionally identified a cohort of 48 patients with TdP, used as
complementary contextual evidence. Recurrent mechanisms included gastrointestinal losses,
diuretics, QT-prolonging drugs, Gitelman syndrome, colistin-induced Bartter-like tubulopathy,
hemodialysis, and alcohol-related depletion. Successful treatment consistently combined trigger
withdrawal, intravenous magnesium sulfate, intensive potassium correction, defibrillation for
unstable episodes, and heart-rate acceleration with pacing or isoproterenol in pause-dependent
TdP. Conclusions: Electrolyte-mediated TdP should be managed as a nephrocardiology
emergency. Electrical stabilization must be coupled with targeted assessment of renal and
extrarenal losses, medication review, and recurrence prevention.
Keywords: torsades de pointes; hypokalemia; hypomagnesemia; long QT; emergency medicine;
nephrology; ventricular arrhythmia; Gitelman syndrome.
generalmente en un contexto de QT
1
. Introducción
corregido (QTc) prolongado [1–5].
La torsades de pointes (TdP) es una
forma característica de taquicardia
ventricular polimórfica que ocurre
sobre un sustrato de repolarización
La
hipopotasemia
y
la
hipomagnesemia
son
dos
determinantes modificables de la
reserva de repolarización. La
disminución del potasio extracelular
reduce corrientes repolarizantes,
ventricular
prolongada.
Su
reconocimiento es crítico porque los
episodios pueden ser autolimitados,
facilita
posdespolarizaciones
manifestarse
recurrente
como
síncope
tempranas y potencia el bloqueo de
IKr inducido por fármacos. La
depleción de magnesio altera la
Na+/K+-ATPasa y otros sistemas de
transporte, favorece inestabilidad
eléctrica y, además, puede hacer
refractaria la corrección de la
hipopotasemia [3,6–9]. Por esta
o
evolucionar
rápidamente a fibrilación ventricular
muerte súbita. En el
electrocardiograma se observa
y
variación cíclica de la amplitud y del
eje de los complejos QRS alrededor
de
la
línea
isoeléctrica,
8
42