Anatomical Reconstructions of the Human Cardiac Venous System using Contrast-computed Tomography of Perfusion-fixed Specimens

Summary

The objective of this research is to recreate and then access the anatomy of the human cardiac venous system using 3D reconstructions generated from contrast-computed tomography scans.

Abstract

A detailed understanding of the complexity and relative variability within the human cardiac venous system is crucial for the development of cardiac devices that require access to these vessels. For example, cardiac venous anatomy is known to be one of the key limitations for the proper delivery of cardiac resynchronization therapy (CRT)¹ Therefore, the development of a database of anatomical parameters for human cardiac venous systems can aid in the design of CRT delivery devices to overcome such a limitation. In this research project, the anatomical parameters were obtained from 3D reconstructions of the venous system using contrast-computed tomography (CT) imaging and modeling software (Materialise, Leuven, Belgium). The following parameters were assessed for each vein: arc length, tortuousity, branching angle, distance to the coronary sinus ostium, and vessel diameter.

CRT is a potential treatment for patients with electromechanical dyssynchrony. Approximately 10-20% of heart failure patients may benefit from CRT². Electromechanical dyssynchrony implies that parts of the myocardium activate and contract earlier or later than the normal conduction pathway of the heart. In CRT, dyssynchronous areas of the myocardium are treated with electrical stimulation. CRT pacing typically involves pacing leads that stimulate the right atrium (RA), right ventricle (RV), and left ventricle (LV) to produce more resynchronized rhythms. The LV lead is typically implanted within a cardiac vein, with the aim to overlay it within the site of latest myocardial activation.

We believe that the models obtained and the analyses thereof will promote the anatomical education for patients, students, clinicians, and medical device designers. The methodologies employed here can also be utilized to study other anatomical features of our human heart specimens, such as the coronary arteries. To further encourage the educational value of this research, we have shared the venous models on our free access website: www.vhlab.umn.edu/atlas.

Protocol

Procedure

Table 1 summarizes the materials used during the process. Figure 1 provides an overview of the process.

1. Specimen and Scan Preparation

1. Obtain the isolated human hearts fresh and subsequently perfusion fix them in 10% buffered formalin in their end-diastolic state.
2. Rinse the hearts to be scanned in water the day before scanning in order to remove the majority of the formalin.
3. Before heading to.......

Discussion

Our laboratory is developing a library of perfusion-fixed heart specimens for various anatomical research studies. To date, we have over 240 preserved specimens. The specific methods we have used to prepare these specimens have been previously described³. The present study describes a novel methodology for mapping the human cardiac venous system and for the development of an anatomical database, which could be used for the design of cardiac devices employed within the vessels.