Novel X-ray image noise reduction technology reduces patient radiation dose while maintaining image quality in coronary angiography

AIMS

The consequences of high radiation dose for patient and staff demand constant improvements in X-ray dose reduction technology. This study assessed non-inferiority of image quality and quantified patient dose reduction in interventional cardiology for an anatomy-specific optimised cine acquisition chain combined with advanced real-time image noise reduction algorithms referred to as 'study cine', compared with conventional angiography.

METHODS

Fifty patients underwent two coronary angiographic acquisitions: one with advanced image processing and optimised exposure system settings to enable dose reduction (study cine) and one with standard image processing and exposure settings (reference cine). The image sets of 39 patients (18 females, 21 males) were rated by six experienced independent reviewers, blinded to the patient and image characteristics. The image pairs were randomly presented. Overall 85 % of the study cine images were rated as better or equal quality compared with the reference cine (95 % CI 0.81-0.90). The median dose area product per frame decreased from 55 to 26 mGy.cm(2)/frame (53 % reduction, p < 0.001).

CONCLUSION

This study demonstrates that the novel X-ray imaging technology provides non-inferior image quality compared with conventional angiographic systems for interventional cardiology with a 53 % patient dose reduction.

Diagnosis and mechanisms of cardiac involvement in patients with systemic sclerosis

Introduction: Systemic sclerosis (SSc) is characterized by fibrosis and vascular abnormalities of skin and internal organs. Cardiac involvement includes coronary artery disease (CAD), pulmonary arterial hypertension (PAH) related right ventricular changes and microvascular disease (MVD). Aims: To characterize the distribution of cardiac alterations and to investigate the mechanisms of the microvascular impairment of SSc patients. Methods: Based on non-invasive investigations, patients were selected for right heart catheterization and intracoronary pressure-wire supplemented coronary angiography. Results: 17 SSc patients (selected from 120 cases) and 17 controls were enrolled. In the “suspected PAH” and the “suspected CAD” groups, PAH was found in 12/20 and 2/10 cases, and coronary artery stenosis in 9/20 and 6/10 cases, respectively. Patients with decreased coronary flow reserve (CFR) had accelerated flow velocity (p<0.05), but myocardial resistance index (IMR) in hyperemia did not differ from patients with normal CFR or from the controls (p=0.292 and p=0.308). The coronary flow velocity of SSc patients correlated to the IMR at baseline (r=0.56, p=0.019). Conclusions: PAH, CAD and MVD show an overlap in symptomatic SSc. The maintained vasodilatation response indicates the paucity of irreversible functional damage of the coronary arterioles. The reduced CFR, the decreased basal IMR and higher velocity pinpoint to possible compensatory vasodilatory mechanisms.