Percutaneous left heart catheterization, including pressure measurements, left ventriculography, coronary angiography and percutaneous coronary interventions (PCI), is nowadays considered the gold standard for the diagnosis, evaluation and treatment of several cardiac diseases (coronary artery disease [CAD], valvular and congenital heart diseases, cardiomyopathies, status post-heart transplant).¹ Although it has shown major benefits, left heart catheterization is not free of complications, as it is an invasive procedure.² The most frequently observed complications are related to access site.³ Such complications, albeit rarely life-threatening, may require additional treatment, including further compression or thrombin injection (for pseudoaneurysms), blood transfusions or vascular surgery.

Bleeding into the alveoli from disruption of the pulmonary capillary lining may cause alveolar hemorrhage and can result from different mechanisms:^1–4
1. Damage secondary to immunologic mechanisms, often associated with a pulmonary capillaritis (i.e., Goodpasture’s syndrome, systemic lupus erythematosus, vasculitides);
2. Direct mechanism or toxic injury (toxin or chemical inhalation, i.e., trimellitic anhydride, isocyanate, phenytoin, penicillamine, hydralazine, mitomycin-C, crack/cocaine use, propylthiouracil);
3. Physical trauma (i.e., pulmonary contusion);
4. Coagulation defects (anticoagulation, thrombocytopenia, disseminated intravascular coagulation);
5. Increased capillary pressure (i.e., mitral stenosis/regurgitation);
6. Other (post-bone marrow transplantation, chemotherapeutic agents).

Aortic stenosis is one of the most common forms of valvular heart disease seen in adults. Despite advances in echocardiography, the evaluation of aortic stenosis continues to be a frequent procedure in the cardiac catheterization laboratory. In order to calculate the aortic valve area using the Gorlin formula,¹ the mean transvalvular pressure gradient across the aortic valve must be measured. To obtain this transvalvular gradient, simultaneous evaluation of the proximal aortic and left ventricular pressures yields the most accurate data. Classically, this has required placing one arterial catheter in the aortic root via one femoral artery, and the second catheter in the left ventricle via the other femoral artery.

In this issue of the Journal, Hays, Lujan, and Chilton describe techniques to accurately measure aortic valve gradient during cardiac catheterization.¹ While noninvasive cardiologists may consider this whole discussion a waste of time — “old cardiology” — there are times when an accurate gradient is important.

Primary percutaneous coronary intervention (PCI) is the best reperfusion strategy in patients with ST-elevation acute myocardial infarction (AMI).¹ This is mainly because it achieves a very high rate of successful recanalization of the infarct-related artery in a wide variety of clinical and angiographic situations,² but also because it virtually eliminates the risk of intracranial bleeding and reduces the incidence of mechanical complications.³

The major cause of mortality in dialysis patients is attributable to cardiovascular diseases.^1,2 The higher prevalence of coronary artery disease in this population is thought to be related to a higher risk factor distribution, platelet thrombogenicity and premature coronary calcification, when compared with nondialysis subjects. Treatment of ischemic heart disease with percutaneous revascularization techniques has remained controversial because of consistent exclusion of dialysis patients from major clinical trials.

The elderly patient with coronary artery disease (CAD) poses unique challenges in clinical management. The basic problem is that there are insufficient data from dedicated clinical trials to provide a framework for decision making. Clinical decisions in elderly patients are thus mainly empiric. The proportion of elderly patients who are included in randomized revascularization trials is much lower than the actual percentage in the CAD population as a whole.¹ Elderly patients in registries and large series exhibit the greatest benefit from interventional procedures when compared to patients in the general population, but they also run the highest risk of complications. Consequently, the younger age groups are preferentially revascularized in clinical practice, a paradoxical utilization of resources in a population that derive the least demonstrable benefit.²

Continued (Part II of II)

Cardiogenic Shock
Although several registries suggest that elderly patients who present with cardiogenic shock have a significant improvement in survival with PCI, neither the SHOCK trial nor the Northern New England Shock Study showed much benefit, and may have shown worse outcomes. These studies demonstrated 34% and 12% absolute differences, respectively in early mortality between elderly patients and younger patients with shock treated with PCI.

Coronary artery bypass graft surgery (CABG) relieves anginal symptoms and decreases morbidity and mortality in patients suffering from coronary artery disease (CAD).^1,2 Unless comorbid diseases are present, guidelines do not recommend the routine use of anti-anginal medication post-CABG.^3,4 However, previous studies suggest that anti-anginal medication is not significantly reduced following CABG. It is also unclear whether functional testing results have an impact on post-CABG prescription patterns. Functional testing is often used to identify graft occlusion, native coronary artery disease progression, and to quantify any residual ischemia. Thus, a positive functional test may suggest the need for more intensive medical therapy or revascularization procedures. In contrast, a negative functional test suggests that anti-anginal medication use could be decreased.