Which of the following services is included in the cardiovascular services of the Medicine section?

Echocardiography is a diagnostic procedure that falls under the cardiovascular services of the Medicine section, as it involves the use of ultrasound to examine the heart's structure and function. This service focuses on non-invasive techniques to assess heart conditions and is primarily performed to evaluate symptoms such as heart murmurs, shortness of breath, or to check for heart conditions like cardiomyopathy or valvular heart disease.

The other options refer to interventions or procedures that are generally categorized differently. Angioplasty is a procedure to open narrowed or blocked blood vessels, typically classified under surgical interventions rather than the Medicine section. Cardiac bypass surgery is a major surgical operation that involves creating a new path for blood flow to the heart, also not part of the non-invasive cardiovascular services. Electrophysiology focuses on the electrical activity of the heart and involves diagnostic tests and interventions that are more specialized and often involve minimally invasive procedures, setting it apart from routine cardiology services like echocardiography.

Thus, echocardiography stands out as the correct answer since it is an integral part of the medical services provided for cardiovascular assessment, focusing on diagnosis rather than invasive treatments.