Effect of External Counterpulsation on Regional Cerebral Blood Flow in Elderly Patients with Transient Ischemic Attack: A SPECT Study

Authors

Zhong-Bang Xu, Tao Pan, Liang Xu, Chen-Hui Zhou, Fu-Chun Sun, Guo-Ying Zhou, Hong Niu

Department of Geriatrics, Second Affiliated Hospital of Nanjing Medical University

Source: usecp.com. Compiled, Reviewed, and Edited by Guo-Ji Gong, US-ECP

Abstract

Background/Context: This study used 99mTC-ECD Single-Photon Emission Computed Tomography (SPECT) to observe changes in regional cerebral blood flow (rCBF) in corresponding areas of 10 elderly patients with transient ischemic attack (TIA) before and after external counterpulsation (ECP) treatment.
Result Summary: The initial rCBF reduction areas showed the following outcomes after ECP: complete recovery in 3 cases, partial improvement in 5 cases, and no change in 2 cases. No deterioration was observed.
Conclusion/Implication: ECP can improve the rCBF reduction areas in most elderly TIA patients.
Keywords: Transient Ischemic Attack (TIA), Regional Cerebral Blood Flow (rCBF)

Materials and Methods

Study Participants

Ten elderly patients with TIA were enrolled: 7 males and 3 females, aged 60 to 72 years (mean ± SD, 65.4±3.8 years).

Diagnostic Criteria

The diagnosis was based on the standard established by the First National Conference on Cerebrovascular Disease in 1986 [1].

Comorbidities

Comorbidities included hypertension (5 cases), hyperlipidemia (7 cases), coronary heart disease (2 cases), degenerative cervical spondylosis (9 cases), and retinal arteriosclerosis (10 cases).

Methods

The first SPECT examination was performed an average of 23±15 days after the last TIA episode. After one course of ECP (36 sessions, 60 minutes each), a second SPECT examination was performed after an average interval of 59±16 days to compare rCBF changes.

Equipment and Operation

A Seimens ZLC3700 SPECT machine was used, with 99mTC-ECD as the tracer [2, 3]. The ECP device was the US-ECP external counterpulsation apparatus, with a cuff pressure of 0.035 to 0.055 mPa.

Efficacy Evaluation Criteria

Complete Recovery: The original rCBF reduction area returned to normal.
Improvement: The original rCBF reduction area showed obvious or partial improvement in blood flow.
No Change (Ineffective): The original rCBF reduction area showed no or only slight improvement in blood flow.

Results

rCBF Reduction Area Distribution at First SPECT

The first SPECT scan showed a total of 31 rCBF reduction areas:

Left side: 15 sites (frontal lobe, 4; temporal lobe, 1; parietal lobe, 4; occipital lobe, 3; basal ganglia, 3).
Right side: 16 sites (frontal lobe, 4; temporal lobe, 2; parietal lobe, 4; occipital lobe, 4; basal ganglia, 2).

Second SPECT Results After ECP Treatment

3 cases of Complete Recovery (involving 9 sites: frontal lobe, 3; temporal lobe, 2; parietal lobe, 2; occipital lobe, 2).
5 cases of Improvement (involving 17 sites: frontal lobe, 4; temporal lobe, 1; parietal lobe, 4; occipital lobe, 4; basal ganglia, 4).
2 cases of No Change (involving 5 sites: frontal lobe, 1; parietal lobe, 2; occipital lobe, 1; basal ganglia, 1).
No case showed deterioration.

Total Effective Rate

The total effective rate was 80% at the patient level (8 out of 10 cases were effective) and 83.9% at the rCBF reduction area level (26 out of 31 sites were effective).

Discussion

Cerebral SPECT perfusion imaging is an advanced and reliable technique for studying rCBF [2, 3]. 99mTC-ECD crosses the blood-brain barrier, and the amount entering the brain tissue is proportional to rCBF, producing clear images.

This study confirms that 80% of elderly TIA patients have rCBF reduction areas after the event, which may represent the pathophysiological basis of TIA, and some patients may progress to full stroke [4].

Animal experiments and clinical studies have proven that ECP can increase carotid artery blood flow [5]. This study provides objective SPECT evidence that ECP significantly improves rCBF reduction areas in elderly TIA patients, with 30% achieving complete recovery and 50% showing improvement, resulting in a total effective rate of 80%. The improvement in rCBF due to ECP may prevent or alleviate the occurrence of complete cerebral stroke.

References

Wang XD, et al. [Diagnostic essential points of various cerebrovascular diseases]. Zhonghua Shen Jing Jing Shen Ke Za Zhi. 1988;21:60.
Dembaccai G, et al. Comparison of 99mTC-ECD and 99mTC-HM-PAD. First human results. J Nucl Med. 1988;29:747.
Sun B, et al. [SPECT cerebral blood flow imaging]. Zhonghua He Yi Xue Za Zhi. 1988;8:71.
Bogousslavsky J, et al. Prolonged hypoperfusion and early stroke after transient ischemic attack. Stroke. 1990;21:40.
Xu ZB, et al. [Effect of external counterpulsation on cerebral blood flow]. Zhonghua Shen Jing Jing Shen Ke Za Zhi. 1990;23:103.