INTRODUCTION
Implantable cardioverter defibrillator (ICD) detects ventricular tachycardia (VT) and ventricular fibrillation (VF) and delivers therapy in the form of overdrive antitachycardia pacing (ATP), low-energy cardioversion, and high-energy defibrillation1. It is indicated for patients at high risk for malignant ventricular tachyarrhythmias (primary prophylaxis) and in patients who have survived from a malignant ventricular tachycardia (secondary prophylaxis)2.
ICD remains an effective therapeutic option to prevent sudden death, with favourable profile in the natural history of cardiac channelopathies (CCh)3, which are inherited cardiac ion channels disorders associated with potential ventricular arrhythmias and sudden death in the presence of a structurally normal heart4, 5. The most prevalent CCh are congenital long QT syndrome (LQTS), Brugada syndrome (BrS) and catecholaminergic polymorphic ventricular tachycardia (CPVT), which account for approximately one-third of unexplained sudden deaths6, 7.
The treatment goal of CCh is to avoid arrhythmias and sudden death and it remains a challenge. Beta-blockers for LQTS and CPVT, and quinidine for BrS, have generally been used for therapeutic optimization, minimizing repolarization changes and also reducing ventricular arrhythmias. In cases of syncope, torsade de pointes or cardiac arrest requiring cardiopulmonary resuscitation, ICD and/or cardiac sympathetic denervation are often the treatment choices8.
With increased awareness of genetic arrhythmogenic disorders, the rate of ICD implantation in young adult population is also increasing. Patients can be submitted to conventional (sub/supra pectoral) ICD implantation or subcostal approach9. The vast majority of devices employ bipolar leads, resulting in less susceptibility to electromagnetic interference (EMI)2.
Many studies assessed if magnetic electrical and electromagnetic fields from dental devices could affect cardiovascular implantable electronic devices (CIEDs). Electric toothbrush, amalgamator, high- and low-speed handpieces, endodontic heat carriers, electric pulp tester, apex locators, wired curing light unit and piezoelectric unit do not altering pacing function10-13. Ultrasonic scalers and ultrasonic cleaning systems could interfere with CIEDs, but those EMI events may not be clinically significant14, 15. Unipolar electrosurgery units produce electromagnetic disturbances that may possibly affect the function of ICD by delivering an unintentional shock10.
However, dental anesthetic management of patients with ICD are limited to case reports16, 17. These patients demand adequate care and analgesia because of the potential risk of life-threatening events (LTE) such as sustained ventricular tachycardias, ICD therapies during the intervention and arrhythmic syncope18. It is crucial to provide a wary dental treatment environment averting triggers for arrhythmic events, such as emotional stress, auditory stimuli or increased vagal tone19, 20. Dentists should obtain a detailed medical history of patients with ICD and preferably with a cardiologist background21.
It is important to emphasize that the use of local dental anesthesia in ICD recipients requires basic knowledge in order to avoid eminent complications in patients with risk of sudden cardiac death. In our previous study22, the use of local dental anesthesia with and without epinephrine in selected stable patients with LQTS and BrS did not result in life-threatening arrhythmias, though the maximum heart rate increased after the use of vasoconstrictor during the anesthesia period. We decided to make a subanalysis in cases with CCh and ICD recipients.
The aim of our study was to ascertain the safety of lidocaine 2% with and without epinephrine 1:100,000 in patients with CCh and ICD.