Review of hereditary angioedema

Hereditary angioedema (HAE) is a rare disease caused by deficiency of C1 esterase inhibitor (C1-INH). It is an autosomal dominant disease caused by a variety of mutations in the C1-INH gene. C1-INH is an important regulator of several pathways. One pathway it affects is the kallikrein–kinin pathway, which results in the generation of bradykinin. Bradykinin is an important mediator of edema. Diagnosis is based on low levels of C1-INH. HAE with normal C1-INH is also recognized in the literature and the pathophysiology is due to another aspect of the pathway being affected leading to increased bradykinin level. Bradykinin results in intermittent swelling of the cutaneous and mucosal surfaces. The swelling usually evolves over several hours and lasts a few days. Location of the swelling can involve any part of the body including fatal laryngeal edema. Newer treatments exist to treat acute attacks and reduce the frequency of future attacks. Earlier diagnosis and treatment of hereditary angioedema can prevent HAE-associated mortality. Statement of novelty: New treatments are used to treat these attacks. These treatments are aimed at patients having a more normal life with hereditary angioedema.

Myocardial protection with enalaprilat in patients unresponsive to ischemic preconditioning during percutaneous coronary intervention

Cardioprotection due to angiotensin enzyme inhibitors is attributed, at least in part, to the inhibition of bradykinin breakdown and the preconditioning effect of the elevated endogenous bradykinin level. We have previously shown that in patients undergoing percutaneous coronary intervention, one 120-second balloon inflation is insufficient to precondition the heart. The objective of the present study was to examine whether the administration of enalaprilat to these patients results in protection. Twenty patients underwent two 120-second coronary artery occlusions separated by a reperfusion interval of 10 min. Ten patients were given 50 µg·min–1 enalaprilat in an intracoronary infusion between the balloon inflations, whereas the others received an infusion of saline. In the latter control patients, there were no significant differences in ST-segment elevation between the consecutive occlusions (peak ST: 1.61 ± 0.17 vs. 1.61 ± 0.16 mV; time to reach 0.5 mV ST elevation: 16 ± 4 vs. 22 ± 7 s; mean ST: 1.03 ± 0.12 vs. 1.02 ± 0.11 mV). In the patients who received enalaprilat before the second balloon inflation, the ST-segment elevation was significantly less pronounced and slower during the second inflation than during the first (peak ST: 1.80 ± 0.18 vs. 1.41 ± 0.19 mV; time to reach 0.5 mV ST elevation: 18 ± 4 vs. 30 ± 4 s; mean ST: 1.04 ± 0.11 vs. 0.85 ± 0.14 mV). We conclude that enalaprilat administered during percutaneous coronary intervention provides protection to patients who do not have a protective response to the initial balloon inflation.