Background: Presence of typical chest pain and normal coronary angiography suggest the possibility of microvascular ischemia of the myocardium as well as other non-cardiac causes that are also likely to decrease heart rate variability (HRV). This raises a question whether poor HRV can predict abnormal elective coronary angiography (ECA).
Aim. To compare HRV in patients with typical chest pain when they are classified according to ECA outcomes.
Methods: The study enrolled 150 patients planned for ECA in the cardiac center of AlShaab Teaching Hospital, Khartoum, Sudan, because of typical chest pain. Following assessment of medical history and clinical examination, Bluetooth ECG transmitter and receiver were used for ECG recording and evaluation of time and frequency domains HRV. ECA confirmed the diagnosis of CAD in 108 patients, who were considered as the test group. The other 42 subjects were considered as a control group after exclusion of CAD.
Results: The M±SD of Ln(pNN10), Ln(pNN20), LnLF and LnHF were significantly higher in subjects with normal angiography compared with CAD patients. However, these statistically significant differences disappeared when the comparison was adjusted for age, gender, BMI and HR of the studied groups.
Conclusions: HRV is comparable in patients with typical chest pain regardless of ECA outcomes.
Relevance for patients: The HRV differences between patients with normal and abnormal ECA is likely to be biased by CAD risk factors like old age, male gender and tachycardia that are known to disturb HRV. The possibility of microvascular ischemia in patients with normal ECA may have attenuated HRV in this group and make it comparable to those suffering from macrovascular ischemia due to CAD.
1 College of Medicine, Qassim University, KSA
2 Nile College of Medicine Khartoum, Sudan
3 Faculty of Medicine, Al Neelain University, Khartoum, Sudan
Mohamed Faisal Lutfi
Department of Physiology - Faculty of Medicine and Health Sciences - Al-Neelain University – Khartoum – Sudan
Mailbox: 12702 – code:11121
Department of Pharmaceutics, Utrecht University, the Netherlands
Department of Pharmaceutics, Jiaxing University Medical College, Zhejiang, China