An important point to recognize is that use of the term “resistance” is controversial and likely misleading for several reasons. First, a drug response must be defined in terms of biomarkers rather than clinical events; patients with atherosclerosis nearly always receive a variety of concomitant treatments, so a clinical event can be regarded as a failure of any or all of these treatments rather than simply an inadequate response to a specific drug. Second, a variety of in vitro tests are available to characterize the response to antiplatelet drugs. However, the responses reported by one test do not necessarily reflect responses reported by others, so categorizing a particular patient as either “responsive” or “resistant” is in part dependent on which test is used. Third, the basal reactivity of platelets before administering either drug may play a large role in determining the final degree of platelet activity after either drug is administered. Finally, relatively stringent criteria for a biomarker's adequacy have been expounded in recent years;6 however, neither the in vitro responses to aspirin nor to clopidogrel have strictly met these requirements. In addition, almost no reports exist concerning the reproducibility of determinations made with any of the tests, and very few reports exist concerning the temporal stability of these estimates. For example, it is unknown whether a patient who is classified as aspirin “resistant” on day 1 will also be “resistant” at the end of a month or a year. In fact, there is reason to suspect that this may not be the case at all.

There is little question that oral antiplatelet agents have found a distinct and nearly universal role in the management of patients with atherosclerotic disease. Aspirin has proven to be an important drug that reduces the complications of virtually all manifestations of atherosclerosis in the cardiac and cerebral circulations.1 The thienopyridines, ticlopidine and clopidogrel, have been useful in managing patients who have undergone intracoronary stent placement2 as well as those suffering from acute coronary syndromes3 and ST segment elevation myocardial infarction.4,5 However, a variety of publications over the past five years have reinforced the concept that the responses of individual patients to these drugs is heterogeneous, and that this heterogeneity may have important clinical consequences. This monograph will review the evidence that such variability not only exists but is also clinically meaningful.
" />

An important point to recognize is that use of the term “resistance” is controversial and likely misleading for several reasons. First, a drug response must be defined in terms of biomarkers rather than clinical events; patients with atherosclerosis nearly always receive a variety of concomitant treatments, so a clinical event can be regarded as a failure of any or all of these treatments rather than simply an inadequate response to a specific drug. Second, a variety of in vitro tests are available to characterize the response to antiplatelet drugs. However, the responses reported by one test do not necessarily reflect responses reported by others, so categorizing a particular patient as either “responsive” or “resistant” is in part dependent on which test is used. Third, the basal reactivity of platelets before administering either drug may play a large role in determining the final degree of platelet activity after either drug is administered. Finally, relatively stringent criteria for a biomarker's adequacy have been expounded in recent years;6 however, neither the in vitro responses to aspirin nor to clopidogrel have strictly met these requirements. In addition, almost no reports exist concerning the reproducibility of determinations made with any of the tests, and very few reports exist concerning the temporal stability of these estimates. For example, it is unknown whether a patient who is classified as aspirin “resistant” on day 1 will also be “resistant” at the end of a month or a year. In fact, there is reason to suspect that this may not be the case at all.

There is little question that oral antiplatelet agents have found a distinct and nearly universal role in the management of patients with atherosclerotic disease. Aspirin has proven to be an important drug that reduces the complications of virtually all manifestations of atherosclerosis in the cardiac and cerebral circulations.1 The thienopyridines, ticlopidine and clopidogrel, have been useful in managing patients who have undergone intracoronary stent placement2 as well as those suffering from acute coronary syndromes3 and ST segment elevation myocardial infarction.4,5 However, a variety of publications over the past five years have reinforced the concept that the responses of individual patients to these drugs is heterogeneous, and that this heterogeneity may have important clinical consequences. This monograph will review the evidence that such variability not only exists but is also clinically meaningful.
"> Author Profile – Methodist Journal
Methodist Journal

IN THIS ISSUE

Adult Congenital Heart Update

Vol 15, Issue 2 (2019)


FEATURED GUEST EDITOR

ISSUE INTRO

The Growing Number of Adults Surviving with Congenital Heart Disease

See More
RECOGNITIONS

Drs. MacGillivray and Lin Take the Lead in Adult Congenital Heart Disease

See More

REVIEW ARTICLES See More

Advanced Cardiac Imaging for Complex Adult Congenital Heart Diseases

149 Fontan Conversions

Anomalous Aortic Origin of a Coronary Artery

Pulmonary Valve Replacement for Tetralogy of Fallot

Management of the Adult with Arterial Switch

Ebstein’s Anomaly

Heart Transplantation in Adults with Congenital Heart Disease

Cholesterol: Can’t Live With It, Can’t Live Without It

CASE REPORTS See More

Simultaneous Transfemoral Mitral and Tricuspid Valve in Ring Implantation: First Case Report with Edwards Sapien 3 Valve

Uneventful Follow-Up 2 Years after Endovascular Treatment of a High Flow Iatrogenic Aortocaval Fistula Causing Pulmonary Hypertension and Right Heart Failure

Device-Related Thrombus: A Reason for Concern?

Retained Coronary Balloon Requiring Emergent Open Surgical Retrieval: An Uncommon Complication Requiring Individualized Management Strategies

MUSEUM OF HMH MULTIMODALITY IMAGING CENTER See More

Do I Look Fat in This? Multimodality Imaging Findings of a Cardiac Lipoma

CLINICAL PERSPECTIVES See More

POINTS TO REMEMBER

The Kidney in Congenital Cyanotic Heart Disease

EXCERPTA

Talking Statins with Antonio Gotto

POINTS TO REMEMBER

Lipids and Renal Disease

EXCERPTA

Addressing the Feedback Loop Between Depression, Diabetes, and Cardiovascular Disease

EDITORIALS

Letter to the Editor in Response to “Cardiac Autonomic Neuropathy in Diabetes Mellitus”

Author Profile

Abdalrahman Ahmed Alghendy, M.D.

Methodist DeBakey Heart & Vascular Center,  Houston Methodist Hospital, Houston, Texas