Physical examination should consist of a thorough cardiac exam, lung exam, and close monitoring of vital signs. Findings on physical exam may include hemodynamic instablity, cannon a wave in jugular venous pulsation, rales in lung fields, lower limbs edema, evidence of sternotomy scar due to previous CABG, and ICD pocket.

Physical findings depend in part on the P-to-QRS relationship with/without signs of AV dissociation.^[1]

• Carotid sinus massage may slow the atrial rate and, in some cases, expose AV dissociation.

• Hemodynamic compromised (hypotension, shock) are often, but not always present.
• Highly inconsistent fluctuations in the blood pressure can occur because of the variability in the degree of left atrial (LA) contribution to LV filling, stroke volume, and cardiac output.

• Intermittent cannon A waves can be observed on examination of the jugular pulsation in the neck, and they reflect simultaneous atrial and ventricular contraction.

• Variability in the occurrence and intensity of heart sounds (especially S1) may also be observed and is heard more frequently when the rate of the tachycardia is slower.
• Look for evidence of preexisting conditions like a pacemaker/AICD or scar mark from previous cardiothoracic surgery.