Arrhythmias: appraisal of symptoms by haemodynamic concepts

Arryhthmias can afflict any heart, even in the absence of disease. Given that Cardiac Output (CO) is a product of heart rate and stroke volume, the end-result of brady- and tachy-arrhythmias is the same: low CO with symptoms of low-output state. In bradyarrhythmias, myocardial inotropy operates maximally but the product of stroke volume and slow heart rate yields a low CO. In tacharryhthmias, myocardial inotropy is redundant because the product of low stroke volume arising from low Diastolic Filling Time (DFT) and heart rate also yields a low CO. The hallmark of extrasystole is the duplex of symptoms: dizziness followed by palpitation.