Comparison of Baseline Heart Rate Variability in Stable Ischemic Heart Disease Patients with and without Stroke in Long-Term Observation.

GOAL: Decreased heart rate variability (HRV) has predictive value in postinfarction as well as in ischemic stroke patients. However, it is unknown if ischemic heart disease (IHD) patients who are at high risk of stroke have different HRV profile. The goal of this study was to compare baseline HRV (traditional and novel indices) in stable IHD patients with and without stroke in long-term observation. METHODS: A total of 139 consecutive patients with stable IHD scheduled for coronary angiography were enrolled. Five-minute electrocardiogram readings were taken. Traditional and novel HRV measures were calculated. After 70.06 ± 4.297 months of follow-up, baseline HRV indices in patients who had had a stroke were compared with indices in patients without the aforementioned cerebrovascular event. RESULTS: During follow-up, 6 patients developed stroke. Compared to patients without such a cerebrovascular event, these patients with stroke had lower values for the following HRV indices: de Hann long-term irregularity (30,521 ± 32,767 versus 46,678 ± 25,328; P < .05), Yeh interval index (.0207 ± .0208 versus .0326 ± .0157; P < .05), Organ BAND (3.0563 ± 3.328 versus 4.515 ± 2.276; P < .05), Dalton standard deviation (SD) (17,887 ± 17,636 versus 29,859 ± 16,478; P < .05), Zugaib short-term variability (.004 ± .00416 versus .00622 ± .00418; P < .05), Zugaib long-term variability (.0161 ± .0151 versus .0247 ± .0115; P < .05), standard deviation of all NN intervals (8,954 ± 8,812 versus 16,724 ± 11,594; P < .05), total power (2,616 ± 4,855 versus 4,678 ± 4,653; P < .05), w2 (.71 ± .338 versus 1.719 ± 1.08; P < .05), w3 (1.399 ± .924 versus 2.552 ± 1.609; P < .05), and w4 (1.367 ± 1.705 versus 2.824 ± 2.027; P < .05). No significant differences in other analyzed indices were observed. CONCLUSIONS: Patients with IHD and stroke in long-term observation have different baseline profiles of HRV indices. Further investigations are needed to assess the usefulness of HRV analysis in stroke risk assessment.

Changes in heart rate variability caused by coronary angioplasty depend on the localisation of coronary lesions.

BACKGROUND: Coronary angioplasty (PTCA) is a common treatment method in patients with coronary heart disease, but its effects on heart rate variability (HRV) have not been well established. AIM: To verify whether the localisation of coronary lesion undergoing PTCA affects HRV parameters. METHODS: Ninety six consecutive individuals underwent elective coronary angiography with subsequent ad hoc successful PTCA. Two five-minute ECG were recorded, one before PTCA and the second 24-hour after PTCA. The HRV indices were determined by means of classical and 'new' mathematical models. RESULTS: The PTCA-induced changes in HRV variables depended on the localisation of dilated lesion. PTCA of the circumflex artery revealed the most significant HRV changes--a decrease in value of domain indices: Yeh DI (0.033+/-0.031 vs. 0.011+/-0.006 un/unitless, p=0.005), Yeh II (0.053+/-0.039 vs. 0.032+/-0.013 un, p=0.017), Organ BAND (9.101+/-9.245 vs. 4.62+/-2.205 bpm/beat per minute, p=0.031), Huey STV (208.821+/-262.248 vs. 76.444+/-35.281 bpm, p=0.013), Dalton MABB (15.733+/-16.575 vs. 7.57+/-4.89 ms, p=0.015), Dalton SD (48.741+/-37.468 vs. 27.759+/-10.533 ms, p=0.015), Zugaib STV (0.0129+/-0.0132 vs. 0.005+/-0.003 un, p=0.005), SDNN (27.204+/-18.592 vs. 21.329+/-32.784 ms, p=0.044), rMSSD (56.239+/-19.751 vs. 51.496+/-43.889 ms, p=0.025) and increased LF/HF (2.384+/-2.072 vs. 5.632+/-5.379 un, p=0.044). Angioplasty of the right coronary artery resulted in decreased AR TP (18.273+/-2.296 vs. 17.085+/-2.256 ms(2), p=0.017) and alteration of the sympathovagal balance of the autonomic nervous system towards predominance of sympathetic activity: AR LF (0.264+/-0.029 vs. 0.284+/-0.040 un, p=0.007), LF/HF (4.310+/-4.457 vs. 6.958+/-7.013 un, p=0.018), HF (0.199+/-0.165 vs. 0.141+/-0.157 un, p=0.031), AR HF (0.647+/-0.043 vs. 0.621+/-0.054 un, p=0.014). PTCA of the left anterior descending artery caused no change. CONCLUSION: Changes in heart rate variability caused by coronary angioplasty depend on the localisation of coronary lesions.