Implantable cardioverter-defibrillator (ICD) provides an exclusive epidemiological tool for evaluation of the earthquake induced cardiac arrhythmias.

In the past decade, earthquakes cause about 60% of all disaster related deaths. High mortality rate after natural disasters reflects the fact that losses caused not only by the destruction of buildings, but also from sudden death due to cardiac arrhythmias.1, 2 Analysis of cardiac arrhythmias before and following a natural disaster was not possible until the invention of the ICD, so very few studies are available on arrhythmia incidence after an earthquake. Right now the implantable cardioverter-defibrillators (ICDs), is used to prevent cardiac arrest in high-risk patients that are at risk for, life-threatening ventricular arrhythmias. ICDs also can keep a record of the abnormal heart’s rhythm when occurs, that would be retrieved during an office visit. Therefore ICDs can also be used to study cardiac arrhythmias before and after great earthquakes. Firstly ICDs were applied to study the occurrence of tachyarrhythmias after the Great East Japan Earthquake on March 11, 2011, devastating the northeastern coast region of Japan. We did the second research by applying the ICDs to study the arrhythmic events following the Iran’s East Azerbaijan Province Earthquake on August 11, 2012. At 16:53 and 17:04 on August 11, 2012 the East Azerbaijan Province in the northwest of Iran was shaken by two great earthquakes measuring 6.3 and 6.4, on the Richter scale, respectively. Earthquakes were completely felt in Tabriz city, about 80 km west to the epicenter of the earthquakes. 300 people died and around 26,000 persons injured and a lot of people became homeless mostly in rural areas.4, 5 Since, Shahid Madani Heart Hospital in Tabriz is a third referral Heart Center in the Northwestern region of Iran, therefore a unique and exclusive opportunity to study the earthquake induced cardiac arrhythmias was created. We evaluated the frequency and severity of arrhythmia episodes and their relation to the imposed psychological stress of the earthquake. The device recordings clearly showed a significant increase in ventricular tachyarrhythmias after the Earthquake. Table 1 Our results, strengthen the hypothetic relation between acute stress and cardiac arrhythmias. So a primary prevention strategy is needed to decrease sudden death after earthquakes, by identifying those at highest risk for mental stress-related cardiac arrhythmias. We hope that the ICDs contribute to the development and progress in Disaster Medicine.

Table 1

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Arrhythmias Total patients in EQa area (n = 98)	Before EQa	After EQa	p value
SVTc (n, %)	15 (15.3)	19 (19.4)	0.4
VT or VFb (n, %)	21 (21.4)	35 (35.7)	0.02

EQ: Earthquake.

VT/VF: Ventricular Tachycardia/Fibrillation.

SVT: supraventricular tachycardia.

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Conflicts of interest

We declare that we have no conflicts of interest.