Managing coronary artery disease in the cancer patient

Interplay between acute coronary syndromes and cancer: insights into pathophysiology, diagnostic challenges, and treatment options

Acute coronary syndromes (ACS) and cancer are among the leading causes of death worldwide. In recent years, increasing evidence has suggested an interplay between these 2 conditions. This article reviews the pathophysiology, diagnostic challenges, and treatment options for ACS and cancer. The interplay between these conditions may be due to environmental, genetic, and metabolic factors. For example, smoking, hypertension, and obesity are risk factors for both ACS and cancer. Diagnosis of ACS and cancer can be challenging because the symptoms of these conditions often overlap. For example, chest pain can be a symptom of both ACS and a neoplasms. Treatment options for ACS and cancer are varied and depend on the type of disease, stage of disease, and individual patient factors. Treatment for ACS may include angioplasty, stenting, or medication therapy. Treatment for cancer may include surgical removal of the tumour, radiation therapy, or chemotherapy.

Management of Acute Coronary Syndrome in Cancer Patients: It's High Time We Dealt with It

Cancer patients have an increased risk of cardiovascular disease and, notably, a significant prevalence of acute coronary syndrome (ACS). It has been shown that an elevated presence of cardiovascular risk factors in this setting leads to an interaction between these two conditions, influencing their therapeutic strategies and contributing to higher mortality. Nonetheless, cancer patients have generally not been evaluated in ACS trials, so that the treatment in these cases is still not fully known. We reviewed the current literature and discussed the best management for these very high-risk patients. The treatment strategy must be tailored based on the cancer type and stage, balancing thrombotic and bleeding risks. When the prognosis is longer than six months, especially if a clinical instability coexists, patients with ACS and cancer should be referred for percutaneous coronary intervention (PCI) as soon as possible. Moreover, an invasive strategy should be preferred in STEMI patients as well as in NSTEMI patients who are considered as high risk. On the contrary, in clinically stable NSTEMI patients, a conservative non-invasive strategy could be adopted, especially in cases of a poor life expectancy and/or of high risk of bleeding. Drug-Eluting-Stents (DES) should be the first choice if an invasive strategy is adopted. Conservative therapy could instead be considered in cancer patients with more stable CAD at an increased risk of major bleeding complications. However, the duration of dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is recommended, but it should be as short as possible, whereas triple antithrombotic therapy is non-advised because it significantly increases the risk of bleeding. ACS management among cancer patients should be based on an accurate evaluation of the risk of thrombosis and bleeding. Future studies focused on choosing optimal strategies in tumor patients with ACS should be performed to treat this subset of patients better.

Impact of stent types on in-hospital outcomes of patients with cancer undergoing percutaneous coronary intervention: A nationwide analysis

BACKGROUND

Cardiovascular disease and cancer frequently coexist, and patients with cancer are at increased risk of cardiovascular events, including myocardial infarction and stroke. However, the impact of stent types on in-hospital outcomes of patients with malignancy is largely unknown.

METHODS

Patients with concomitant diagnosis of cancer undergoing PCI between January 2005 and December 2014 were identified in the National Inpatient Sample. They were then categorized into those who have undergone coronary stenting with bare-metal stent (BMS) or drug-eluting stent (DES). Primary outcomes were in-hospital mortality and stent thrombosis. Adjusted and unadjusted analysis was employed on appropriate variables of interest.

RESULTS

8755 patients were included in the BMS group and 11,611 patients in the DES group. Following propensity matching, 4313 patients were randomly selected in both groups using a 1:1 ratio. There was high use of BMS stent in cancer patient (BMS 43.0%, DES 57.0%) compared to general population (BMS 23.2%, DES 76.8%). When comparing BMS to DES group, there was no statistically significant difference in mortality (4.7% vs. 3.8%, p = 0.097), acute kidney injury (11.3% vs. 10.6%, p = 0.425), bleeding complications (3.50% vs. 3.45%, p = 0.914), and length of hospital stay (5.4% vs. 5.2%, p = 0.119). However, an increased incidence of stent thrombosis was observed in the DES group (4.26% vs. 3.01%, p = 0.002).

CONCLUSION

A higher incidence of BMS placement was noted in patients with cancer than in the general population. Paradoxically there was a high incidence of stent thrombosis in the DES group without increasing mortality.

Clinical outcome of cardiac surgery in patients with remitted or active hepatocellular carcinoma

PURPOSE

Hepatocellular carcinoma (HCC) is one of the most common primary cancers worldwide. HCC has unique characteristics such as co-existing chronic liver damage and a high recurrence rate. A negative impact on the surgical outcome due to these backgrounds could be expected. We aimed to evaluate the clinical outcomes of cardiac surgery in these patients.

METHODS

Between January 2000 and December 2019, 16 patients with remitted cancer and 5 patients with active HCC who underwent open heart surgery were studied. The clinical data were retrospectively evaluated from hospital records. Follow-up information was collected via telephone interviews.

RESULTS

The major cause of HCC was viral hepatitis. Eighteen patients (86%) were classified as having Child-Pugh class A cirrhosis. The mean model of end-stage liver disease (MELD) score was 7.2 ± 5.2. There was no 30-day mortality. During follow-up, 11 patients died due to HCC. The 1-, 3-, and 5-year survival rates were 80.0, 42.5, and 22.3%, respectively. A univariate analysis identified a higher preoperative MELD score and lower serum cholinesterase levels as prognostic factors for long-term survival.

CONCLUSION

We could safely perform cardiac surgery in selected patients with remitted and active HCC. The postoperative life expectancy of these patients was limited but acceptable.

Effect of primary percutaneous coronary intervention on in-hospital outcomes among active cancer patients presenting with ST-elevation myocardial infarction: a propensity score matching analysis

AIMS

Primary percutaneous coronary intervention (pPCI) is the gold standard, guideline-recommended revascularization strategy in patients presenting with ST-elevation myocardial infarction (STEMI). However, there are limited data on its use and effectiveness among patients with active cancer presenting with STEMI.

METHODS AND RESULTS

All STEMI hospitalizations between 2004 and 2015 from the National Inpatient Sample were retrospectively analysed, stratified by cancer type. Propensity score matching was performed to estimate the average treatment effect of pPCI in each cancer on in-hospital adverse events, including major adverse cardiovascular and cerebrovascular events (MACCE) and its individual components, and compare treatment effect between cancer and non-cancer patients. Out of 1 870 815 patients with STEMI, 38 932 (2.1%) had a current cancer diagnosis [haematological: 11 251 (28.9% of all cancers); breast: 4675 (12.0%); lung: 9538 (24.5%); colon: 3749 (9.6%); prostate: 9719 (25.0%)]. Patients with cancer received pPCI less commonly than those without cancer (from 54.2% for lung cancer to 70.6% for haematological vs. 82.3% in no cancer). Performance of pPCI was strongly associated with lower adjusted probabilities of MACCE and all-cause mortality in the cancer groups compared with the no cancer group. There was no significant difference in estimated average pPCI treatment effect between the cancer groups and non-cancer group.

CONCLUSION

Primary percutaneous coronary intervention is underutilized in STEMI patients with current cancer despite its significantly lower associated rates of in-hospital all-cause mortality and MACCE that is comparable to patients without cancer. Further work is required to assess the long-term benefit and safety of pPCI in this high-risk group.

Cancer treatment resumption in patients with new-generation drug-eluting stents

OBJECTIVE

Percutaneous coronary intervention (PCI) with new-generation drug-eluting stents (DESs) may provide survival benefits to the cancer population undergoing PCI by expediting cancer treatment due to improved safety profile. We aimed to assess the safety of starting or resuming cancer treatment within 6 months of DES placement. We also compared the impact of different DES types on the overall survival (OS) in cancer patients and to identify a safe threshold for dual antiplatelet therapy (DAPT) discontinuation.

METHODS

Cancer patients at our institution undergoing PCI with DES from December 2014 to June 2017 were included. Baseline demographics, DAPT duration, malignancy type, stage, and treatment were retrospectively analyzed. Univariate Cox regression was used to pinpoint baseline characteristics that correlated with OS. Survivorship was determined by Kaplan-Meier analysis, and the log-rank test was used to compare OS among DES types.

RESULTS

Seventy-five patients were included. Of these, 45 had biodegradable polymer DES (Synergy) and 30 patients had durable polymer DES (Resolute Integrity, Xience, Ion, or Promus). Mean duration of follow-up was 1367 ± 334 days. There were two minor bleeding complications. No statistically significant differences in OS were found among different stent brands. Discontinuation of aspirin, early P2Y12 inhibitor discontinuation, and advanced cancer were significantly associated with OS. DAPT discontinuation <6 months after PCI was not associated with stent thrombosis or in-stent restenosis. There were two major adverse cardiac events: one in-stent restenosis while on DAPT for >12 months (attributed to radiation-induced heart disease) and one myocardial infarction and death. Of patients who resumed or started cancer treatment (chemotherapy, radiation therapy, or surgery) after PCI, all but one did so within 6 months of PCI, and most of them as early as 2 weeks.

CONCLUSION

Patients may resume cancer treatment <6 months after PCI. We suggest that DAPT may be safely interrupted as early as 6 months, but additional longitudinal studies are needed.

Impact of Incident Cancer on Short-Term Coronary Artery Disease-Related Healthcare Expenditures Among Medicare Beneficiaries

Background: Healthcare spending for coronary artery disease (CAD)-related services is higher than for other chronic conditions. Diagnosis of incident cancer may impede management of CAD, thereby increasing the risk of CAD-related complications and associated healthcare expenditures. This study examined the relationship between incident cancer and CAD-related expenditures among elderly Medicare beneficiaries. Patients and Methods: A retrospective longitudinal study was conducted using the SEER-Medicare linked registries and a 5% noncancer random sample of Medicare beneficiaries. Elderly fee-for-service Medicare beneficiaries with preexisting CAD and with incident breast, colorectal, or prostate cancer (N=12,095) or no cancer (N=34,237) were included. CAD-related healthcare expenditures comprised Medicare payments for inpatient, home healthcare, and outpatient services. Expenditures were measured every 120 days during the 1-year preindex and 1-year postindex periods. Adjusted relationship between incident cancer and expenditures was analyzed using the generalized linear mixed models. Results: Overall, CAD-related mean healthcare expenditures in the preindex period accounted for approximately 32.6% to 39.5% of total expenditures among women and 41.5% to 46.8% among men. All incident cancer groups had significantly higher CAD-related expenditures compared with noncancer groups (P<.0001). Men and women with colorectal cancer (CRC) had 166% and 153% higher expenditures, respectively, compared with their noncancer counterparts. Furthermore, men and women with CRC had 57% and 55% higher expenditures compared with those with prostate or breast cancer, respectively. Conclusions: CAD-related expenditures were higher for elderly Medicare beneficiaries with incident cancer, specifically for those with CRC. This warrants the need for effective programs and policies to reduce CAD-related expenditures. Close monitoring of patients with a cancer diagnosis and preexisting CAD may prevent CAD-related events and expenditures.

Association between red blood cell distribution width and long-term mortality among patients undergoing percutaneous coronary intervention with previous history of cancer

Background: The number of patients suffering from coronary heart disease with cancer is rising. There is scarce evidence concerning the biomarkers related to prognosis among patients undergoing percutaneous coronary intervention (PCI) with cancer. Thus, the aim of this study was to investigate the association between red blood cell distribution width (RDW) and prognosis in this population.Methods: A total of 172 patients undergoing PCI with previous history of cancer were enrolled in this retrospective study. The endpoint was long-term all-cause mortality. According to tertiles of RDW, the patients were classified into three groups: Tertile 1 (RDW <12.8%), Tertile 2 (RDW ≥12.8% and <13.5%) and Tertile 3 (RDW ≥13.5%).Results: During an average follow-up period of 33.3 months, 29 deaths occurred. Compared with Tertile 3, mortality of Tertile 1 and Tertile 2 was significantly lower in the Kaplan-Meier analysis. In multivariate Cox regression analysis, RDW remained an independent risk factor of mortality (HR: 1.938, 95% CI: 1.295-2.655, p < 0.001). The all-cause mortality in Tertile 3 was significantly higher than that in Tertile 1 (HR: 5.766; 95% CI: 1.426-23.310, p = 0.014).Conclusions: An elevated RDW level (≥13.5%) was associated with long-term all-cause mortality among patients undergoing PCI with previous history of cancer.

Optimal management of coronary artery disease in cancer patients

Owing to early diagnosis and rapid development of treatments for cancers, the five-year survival rate of all cancer types has markedly improved worldwide. Over time, however, there has been an increase in the number of cancer patients who develop coronary artery disease (CAD) due to different causes. First, many risk factors are shared between cancer and CAD. Second, inflammation and oxidative stress are common underlying pathogeneses in both disorders. Lastly, cancer therapy can result in endothelial injury, coronary artery spasm, and coagulation, thereby increasing the risk of CAD. As more cancer patients are being diagnosed with CAD, specialized cardiac care should be established to minimize the cardiovascular mortality of cancer survivors.

Nonadherence to Statins and Antihypertensives and Hospitalizations Among Elderly Medicare Beneficiaries With Incident Cancer

Background: Incident cancer diagnosis may increase the risk of coronary artery disease (CAD)-related hospitalizations, especially in older individuals. Adherence to statins and/or angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin II receptor blockers (ARBs)/β-blockers reduces CAD-related hospitalizations. This study examined the relationship between medication adherence and CAD-related hospitalizations immediately following cancer diagnosis. Patients and Methods: A retrospective observational longitudinal study was conducted using SEER-Medicare data. Elderly Medicare fee-for-service beneficiaries with preexisting CAD and incident breast, colorectal, or prostate cancer (N=12,096) were observed for 12 months before and after cancer diagnosis. Hospitalizations measured every 120 days were categorized into CAD-related hospitalization, other hospitalization, and no hospitalization. Medication adherence was categorized into 5 mutually exclusive groups: adherent to both statins and ACEIs/ARBs/β-blockers (reference group), not adherent to both statins and ACEIs/ARBs/β-blockers, adherent to either statins or ACEIs/ARBs/β-blockers, use of one medication class and adherent to that class, and use of one medication class and not adherent to that class. The relationship between medication adherence and hospitalization was analyzed using repeated measures multinomial logistic regressions. Inverse probability treatment weights were used to control for observed group differences among medication adherence categories. Results: Adherence to both statins and ACEIs/ARBs/β-blockers was estimated at 31.2% during the 120-day period immediately following cancer diagnosis; 13.7% were not adherent to both medication classes during the same period, and 27.4% had CAD-related hospitalizations immediately after cancer diagnosis, which declined to 10.6% during the last 4 months of the postdiagnosis period. In the adjusted analyses, those not adherent to both statins and ACEIs/ARBs/β-blockers were more likely to have CAD-related hospitalization compared with those adherent to both medication classes (adjusted odds ratio, 1.82; 95% CI, 1.72-1.92; P<.0001). Conclusions: Given the complexity of interaction between CAD and cancer, it is important to routinely monitor medication adherence in general clinical practice and to provide linkages to support services that can increase medication adherence.

Management of CAD in Patients with Active Cancer: the Interventional Cardiologists' Perspective

PURPOSE OF REVIEW

Coronary artery disease in patients with active cancer presents particular challenges for clinicians, as optimum management is required in order to treat the underlying malignancy and to reduce morbidity and mortality associated with cardiovascular diseases. Special considerations must be made in respect to either primary or secondary thrombocytopenia, the presence of coagulopathies and the propensity of bleeding, vascular access complications, and increased risk of stent thrombosis.

RECENT FINDINGS

In presence of acute coronary symptoms, the cardio-oncology team has to make a complex decision between conservative medical management or early angiography (within 24 h) and revascularization. There is a lack of reliable data on the outcomes of patients with active cancer who undergo invasive procedures for the diagnostic and treatment of coronary artery disease. Cardiac catheterization recommendations in cancer patients are being currently elaborated by cardio-oncologists in order to improve the overall survival in cancer patients with coronary artery disease.

"Bringing on the light" in a complex clinical scenario: Optical coherence tomography-guided discontinuation of antiplatelet therapy in cancer patients with coronary artery disease (PROTECT-OCT registry)

BACKGROUND

Cancer patients with recently placed drug-eluting stents (DESs) often require premature dual antiplatelet therapy (DAPT) discontinuation for cancer-related procedures. Optical coherence tomography (OCT) can identify risk factors for stent thrombosis such as stent malapposition, incomplete strut coverage and in-stent restenosis and may help guide discontinuation of DAPT.

METHODS

We conducted a single-center prospective study in cancer patients with recently placed (1-12 months) DES who required premature DAPT discontinuation. Patients were evaluated with diagnostic coronary angiogram and OCT. Individuals with appropriate stent strut coverage, expansion, apposition, and absence of in-stent restenosis or intraluminal masses were considered low risk and transiently discontinued DAPT to allow optimal cancer therapy. Patients who did not meet all these criteria were considered high risk and underwent further endovascular treatment when appropriate and bridging with low-molecular weight heparin. The incidence of adverse cardiovascular events was assessed after the procedure and at 12 months.

RESULTS

A total of 40 patients were included. Twenty-seven patients (68%) were considered low risk by OCT criteria and DAPT was transiently discontinued. Thirteen patients (32%) were considered high risk with one or more OCT findings: uncovered stent struts (4 patients, 10%); stent underexpansion (3 patients, 8%); malapposition (8 patients, 20%); in-stent restenosis (2 patients, 5%). The high-risk patients with uncovered stent struts and malapposition underwent additional stent dilatation. There were no cardiovascular events in the low-risk group. One myocardial infarction occurred in the high-risk group. Fourteen non-cardiac deaths were registered before 12 months due to cancer progression or cancer therapy.

CONCLUSION

OCT imaging allows identification of low-risk cancer patients with DES placed who may safely discontinue DAPT and proceed with cancer-related surgery or procedures.

Feasibility and efficacy of simultaneous off-pump coronary artery bypass grafting and esophagectomy in elderly patients

INTRODUCTION

To analyze the outcomes of off-pump coronary artery bypass grafting (OPCABG) and esophagectomy simultaneously for patients with coronary artery disease (CAD) and coexisting esophageal cancer.

METHODS

Twenty-two patients with CAD and coexisting esophageal cancer underwent combined surgical interventions were subjected to the study. OPCABG was performed first, followed by esophagectomy. All the corresponding data including clinicopathological characteristics and postoperative outcomes were all investigated.

RESULTS

All the combined procedures were performed successfully. The average number of grafts was 2.36. Tumors were located at the middle third of the esophagus in 5 patients, at the lower third of the esophagus in 8 patients, at the esophageal gastric junction (EGJ) in 9 patients, respectively. The operations were carried out through a left lateral thoracotomy approach in 21 patients while a median sternotomy and left lateral thoracotomy approach was used in 1 patient for his condition rapidly worsened. Postoperatively, pneumonia occurred in 4 patients (18.2%). During the follow-up, three patients died of cancer metastasis /recurrence (6, 18, 37 months) and one died of pneumonia (1 month). The cumulative 5 years survival rate is 52.9%.

CONCLUSIONS

The combined procedure of OPCABG and esophagectomy is a safe and effective treatment option for patients with severe CAD and esophageal cancer.

Ischemic Heart Disease: Special Considerations in Cardio-Oncology

OPINION STATEMENT

The interplay and balance between the competing morbidity and mortality of cardiovascular diseases and cancer have a significant impact on both short- and long-term health outcomes of patients who survived cancer or are being treated for cancer. Ischemic heart disease in patients with cancer or caused by cancer therapy is a clinical problem of emerging importance. Prompt recognition and optimum management of ischemic heart disease mean that patients with cancer can successfully receive therapies to treat their malignancy and reduce morbidity and mortality due to cardiovascular disease. In this sense, the presence of cancer and cancer-related comorbidities (e.g., thrombocytopenia, propensity to bleed, thrombotic status) substantially complicates the management of cardiovascular diseases in cancer patients. In this review, we will summarize the current state of knowledge on the management strategies for ischemic disease in patients with cancer, focusing on the challenges encountered when addressing these complexities.

Analysis of the costs and quality of cardiovascular care in oncological monitoring

Objective:

To analyze the health care costs specifically related to cardiovascular diseases, which were spent by patients of a private healthcare provider in southern Brazil, after their diagnosis of cancer.

Method:

We developed an observational, cross-sectional, retrospective study, with a qualitative-quantitative strategy, through the activity of analytical internal audit of medical accounts.

Results:

860 accounts from 2012 to 2015 were analyzed, 73% referred to female users, with average age of 62.38 years, and a total direct cost of BRL 241,103.72. There was prevalence of 37% of breast cancer, 15% of prostate cancer and 9% of colon cancer. In relation to the cardiovascular care, 44% were consultations, 44% were complementary exams, 10% were emergency care, and 3% were hospitalizations. Regarding the health care costs with cardiovascular services, higher costs were in hospitalizations (51%), followed by complementary exams (37%), consultations (8%) and emergency care (4%).

Conclusion:

The cancer survivors commonly use health care in other specialties such as cardiology, and the main cost refers to hospitalization. It is recommended to invest in prevention (consultation and complementary exam) as well as in programs of chronic disease management to reduce costs and improve the quality of health care.

SCAI Expert consensus statement: Evaluation, management, and special considerations of cardio-oncology patients in the cardiac catheterization laboratory (endorsed by the cardiological society of india, and sociedad Latino Americana de Cardiologıa intervencionista)

In the United States alone, there are currently approximately 14.5 million cancer survivors, and this number is expected to increase to 20 million by 2020. Cancer therapies can cause significant injury to the vasculature, resulting in angina, acute coronary syndromes (ACS), stroke, critical limb ischemia, arrhythmias, and heart failure, independently from the direct myocardial or pericardial damage from the malignancy itself. Consequently, the need for invasive evaluation and management in the cardiac catheterization laboratory (CCL) for such patients has been increasing. In recognition of the need for a document on special considerations for cancer patients in the CCL, the Society for Cardiovascular Angiography and Interventions (SCAI) commissioned a consensus group to provide recommendations based on the published medical literature and on the expertise of operators with accumulated experience in the cardiac catheterization of cancer patients.

Cancer in heart disease patients: what are the limitations in the treatment strategy?

Cardiovascular disease and cancer are leading causes of morbidity and mortality, and can both be present in one patient. In patients with simultaneous disease, the most threatening disease should be treated first. This is usually heart disease, but this can pose specific problems. If percutaneous coronary intervention is preferred, bleeding and thrombotic tendencies have to be taken into account in the subsequent treatment of the malignancy. With coronary artery bypass grafting, the advantages and disadvantages of one- or two-stage procedures, and the use of extracorporeal circulation have to be balanced. Development of heart disease after treatment of malignancy could be due to radiotherapy and chemotherapy. The effects of these cancer treatments have to be taken into account for the treatment options of the heart disease and the postoperative prognosis.

Evolving management of patients treated by drug-eluting stent: prevention of late events

SUMMARY

Drug eluting stents (DES) were introduced in clinical practice to overcome the problem of in-stent restenosis (ISR) that limited the overall efficacy of percutaneous coronary revascularization with bare metal stent (BMS). Long-term outcome data confirm a sustained benefit of DES as compared with BMS. However, this benefit is mainly evident in the first year of follow-up. Indeed, DES-related events may extend over this time, due to late events (late ISR and/or very late stent thrombosis). Prevention of late failure of DES may become a specific therapeutic target.

In-stent thrombosis after carotid artery stenting despite sufficient antiplatelet therapy in a bladder cancer patient

In-stent thrombosis (IST) after carotid artery stenting (CAS) is a rare but potentially devastating complication. We present a case of early IST after CAS despite sufficient antiplatelet therapy in a patient with bladder cancer. A 77-year-old man under preventive triple antiplatelet therapy underwent CAS without any intra- or periprocedural complications. However, the patient developed a large asymptomatic IST 6 days after CAS. Anticoagulant therapy with argatroban was reintroduced to treat IST concomitant with antiplatelet agents. Subsequently, the IST shrank and disappeared without any thrombotic symptoms. Malignancy is regarded as an acquired thrombophilic condition associated with a significant risk of thrombosis. In the field of coronary stents, cancer is associated with a significant increasing risk of IST. The cause of IST in our case was possibly related in hypercoagulable state because of the patient's cancer. Attention for IST should be paid in CAS cases with these risk factors, and repeated examination is recommended.

Surgical management of coronary artery disease associated with malignancy

Surgical management of patients with combined coronary artery disease and malignancy remains a challenge. In this review the time of surgical intervention, whether to treat the malignancy or the coronary artery disease first, and which bypass technique should be used during myocardial revascularization are reviewed to determine the most optimal strategy to manage patients who require coronary surgical revascularization and present with an underlying malignancy.

Thymoquinone-induced platelet apoptosis

Thymoquinone (TQ) is a nutrient with anticarcinogenic activity that stimulates suicidal death of tumor cells. Moreover, TQ triggers suicidal death of erythrocytes or eryptosis, an effect at least partially due to increase in cytosolic Ca(2+) activity and ceramide formation. The present experiments explored whether TQ influences apoptosis of blood platelets. Cell membrane scrambling was determined utilizing Annexin V binding to phosphatidylserine exposing platelets, cytosolic Ca(2+) activity utilizing Fluo 3-AM fluorescence, caspase activity utilizing immunofluorescence and Western blotting of active caspase-3 and inactive procaspase-3, mitochondrial potential utilizing DiOC(6) fluorescence and ceramide by FACS analysis of ceramide-binding antibodies. A 30 min exposure to TQ (≥5 µM) was followed by Annexin V binding, paralleled by caspase activation, increase of cytosolic Ca(2+) activity, mitochondrial depolarization, and ceramide formation. P-selectin exposure and integrin α(IIb) β(3) activation did not increase in response to TQ. Nominal absence of extracellular Ca(2+) blunted but did not fully abolish the TQ-induced activation of caspase-3. The effects of TQ on platelets are significantly abolished with phosphoinositide-3 kinase (PI3K) inhibitor wortmannin and G-protein coupled receptor (GPCR) inhibitor pertussis toxin treatment prior to TQ stimulation. In conclusion, TQ triggers suicidal death of blood platelets in a PI3K-dependent manner, possibly through a GPCR family receptor; an effect paralleled by increase of cytosolic Ca(2+) activity, ceramide formation, mitochondrial depolarization, and caspase-3 activation.