Table 1.

Summary detailing advantages and disadvantages of catheter- and injection-based myocardial delivery strategies

Delivery route	Advantages	Disadvantages
Intracoronary delivery	•Minimally invasive •Established clinical history •Relatively inexpensive •Low risk of myocardial damage	•Potential for induction of arterial obstruction •Not established for chronic disease states •Limited in cases of severe vascular stenosis •Largely excludes biomaterial-based therapies
Intrapericardial delivery	•Able to facilitate payload delivery to the entire heart •Confers local and global therapeutic benefits •Limits off-target drug accumulation	•Requires puncturing the pericardium •Relatively low clinical familiarity •Diminished pericardial fluid volume elevates risk of surgical damage
Intramyocardial delivery: Transepicardial route	•High spatial precision/regional targeting •Facilitates surgical control of perforations or hemorrhage •Can be used to deliver in situ forming gels	•Invasive procedure requiring prolonged recovery •Risk of coronary arterial injuries •Thin left ventricle elevates risk of cardiac perforation
Intramyocardial delivery: Transendocardial route	•Enhanced myocardial payload retention compared with intracoronary delivery •Enabling technologies with enhanced steering/targeting under development by industry	•Moderate risk of cardiac perforation and stroke •Minimal demonstration of associated improvement in payload efficacy