Usefulness of multidetector computed tomography coronary venous angiography examination before cardiac resynchronization therapy

Cardiac CT in CRT as a Singular Imaging Modality for Diagnosis and Patient-Tailored Management

Between 30-40% of patients with cardiac resynchronization therapy (CRT) do not show an improvement in left ventricular (LV) function. It is generally known that patient selection, LV lead implantation location, and device timing optimization are the three main factors that determine CRT response. Research has shown that image-guided CRT placement, which takes into account both anatomical and functional cardiac properties, positively affects the CRT response rate. In current clinical practice, a multimodality imaging approach comprised of echocardiography, cardiac magnetic resonance imaging, or nuclear medicine imaging is used to capture these features. However, with cardiac computed tomography (CT), one has an all-in-one acquisition method for both patient selection and the division of a patient-tailored, image-guided CRT placement strategy. This review discusses the applicability of CT in CRT patient identification, selection, and guided placement, offering insights into potential advancements in optimizing CRT outcomes.

Usefulness of Pre-Procedural Imaging of the Coronary Venous System With Coronary Angiography Before Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT) is a treatment modality for selected patients with refractory heart failure. We intended to examine the usefulness of coronary venous system imagining with conventional coronary angiogram before the CRT implantation procedure. A total of 180 patients were scheduled for CRT and were prospectively randomized 1:2 into 2 groups. Group 1 (n = 60) received standard CRT procedure without the guidance of selective left coronary angiography. In group 2 (n = 120), CRT implantation was accomplished with the guidance of the preprocedural coronary angiography. We compared the 2 groups in terms of the total implantation time, total fluoroscopy time, the amount of contrast medium used, and cumulative radiation exposure. The total implantation and fluoroscopy times, the amount of contrast medium used, and cumulative radiation exposure were significantly less in group 2 compared with group 1 (53 ± 7 vs 66 ± 9 minutes, 11 ± 3 vs 20 ± 5 minutes, 24 ± 8 vs 42 ± 14 mL, 26 192 ± 6658 vs 37 388± 9064 mGy cm², and 253 ± 49 vs 392 ± 79 mGy, P < .0001, respectively). We concluded that coronary angiography prior to CRT implantation is useful in simplifying the procedure, saving time, reducing radiation exposure, and reducing contrast use.

Association between changes in coronary artery circulation and cardiac venous retention: a lesson from cardiac computed tomography

To use computed tomography (CT) image data to measure a potential association between the implantation of coronary artery bypass grafts (CABG) and changes in the coronary venous system has not yet been examined. In 112 (aged 59.4 ± 9.0; 45F) patients (pts.), a 64-slice CT angiography was performed. Patients were divided into 2 groups: CABG (56 pts.) and control (56 pts.)—without changes in coronaries. In each case, ten multi-planar reconstructions (MPR) and 3D volume rendering reconstructions using a 2 mm layer with ECG-gating, helical pitch: 12.8; rotation time: 0.4 s and average tube voltage: 135 kV at 380 mA. The visualization of the coronary veins was independently graded by 2 experts trained in CT. In the CABG group, the average number of visible coronary veins was 5.3 ± 1.3, while in the control group it was 3.1 ± 1.1 (p < 0.001). Statistical differences were also observed for the following coronary veins: posterolateral (control 2.1 ± 1.9 vs. CABG 2.9 ± 1.9; p < 0.05), lateral (control 2.2 ± 1.7 vs. CABG 3.1 ± 1.3; p < 0.01) and anterolateral (control 0.5 ± 0.9 vs. CABG 1.3 ± 1.0; p < 0.001). Implantation of CABG influences the coronary venous system. In patients after CABG, the number of identifiable coronary veins is significantly higher as compared to that in subjects without changes in coronaries. This might suggest an association between changes in coronary artery circulation and cardiac venous retention.

Coronary venous retention-a feature in heart failure as evidenced by mean of cardiac computed tomography

BACKGROUND

Whether the functional status of the heart can influence the coronary venous system itself has not yet been examined. In order to answer this question, we used multislice computed tomography (CT) imaging.

PURPOSE

To answer the question of whether the heart failure (HF) is associated with significant anatomical changes in the coronary venous system?

METHODS

In 136 (aged 56.6 ± 11.5) patients, a 64-slice CT was performed. Patients were divided into three groups according their ejection fraction. In each case, nine 3D volume rendering reconstructions, using a 2-mm layer with electrocardiographic-gating, were created at 0% to 90% R-R intervals (step 10%). The visualization of coronary veins (CVs) was graded independently by two experts trained in multislice computed tomography on a 0-5 point scale (0-not visible/lack of vein; 5-smoothly bordered vascular structure).

RESULTS

The average number of visible CVs per case was 3.44 in the HF group and 2.72 in patients with a normal ejection fraction (P = 0.0246). The statistical correlation between a reduction in ejection fraction and the increase in the number of veins was found (r =-0.2446, P < 0.05). For two of seven common variants of the coronary venous system at least two target veins (posterolateral and lateral) for cardiac resynchronization were presented.

CONCLUSIONS

The statistically higher number of veins in patients with heart failure may suggest an association between a failing heart and cardiac venous retention.