New-onset palpitations in general practice: assessing the discriminant value of items within the clinical history

Palpitations are non-specific, with less than half of patients experiencing palpitations having a cardiac arrhythmia. Currently it seems that there is little evidence available to assist GPs in discriminating between patients complaining of palpitations who have significant cardiac arrhythmias and those who do not.

Our aim was to estimate discriminant functions for specific items of clinical information in relation to the categorization of a patient (aged over 18 years) with a symptom of new-onset palpitations presenting to primary care.

A network of 62 GPs spread amongst 36 practices agreed to recruit patients with new-onset palpitations over the course of a 9-month study period. Patients consenting to be involved in the study were asked a number of questions, focusing particularly on the medical history, and were requested to complete a Hospital Anxiety and Depression Scale. Each patient was also provided with a RhythmCard cardiac event recorder for up to 2 weeks and was asked to record their heart rhythm if they experienced palpitations. Odds ratios (adjusted for age and sex) were used to compare the clinical information obtained from patients with the final diagnosis.

Of the 139 patients with palpitations presenting to GPs, it would appear that males [odds ratio = 2.1 (1.0-4.5)], those with regular palpitations [odds ratio = 2.5 (1.0-5.8)], those experiencing palpitations at work [odds ratio = 3.0 (1.3-7.2)] and those experiencing palpitations affected by sleeping (odds ratio = 3.3 (1.4-7.7)] were more likely to have a cardiac cause for their palpitations. Similar findings were made in an analysis focusing solely on the 81 patients with a RhythmCard result. Furthermore, amongst this group, it is interesting to note that patients with regular palpitations were more than twice as likely to have a 'significant' cardiac arrhythmia as a cause for their palpitations. There were suggestions of dose-response effects between the rate of the palpitation, the duration of the palpitation and the likelihood of it being a 'significant' arrhythmia.

This study provides some information on the characteristics of patients reporting palpitations to GPs who may have 'significant' cardiac arrhythmias. Based on this work, we believe that a larger community-based study would be worthwhile and would provide useful and useable clinical discriminant information for GPs in the settings where they work and amongst the types of patients they encounter.