Marc Carrier, MD
@marccarriermd.bsky.social
190 followers 58 following 60 posts
Hematologist 🩸| Blood clot lover | Division Head @Ottawa Hospital | Senior Scientist @OHRI | Professor of Medicine at University of Ottawa
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Reposted by Marc Carrier, MD
psifoundation.bsky.social
Drs. Kevin Durr, Alexandre Tran & Marc Carrier's @marccarriermd.bsky.social study on personalized risk stratification and reduction of venous thromboembolism among critically ill patients: www.psifoundation.org/funded-resea... #WorldThrombosisDay #ThrombosisResearch @ottawahospital.on.ca
Funded Research - PSI Foundation
List of projects funded by PSI Foundation.
www.psifoundation.org
marccarriermd.bsky.social
Radiotherapy may independently increase the risk of venous thromboembolism. 🩸⚡

This review in @rpth.bsky.social unpacks mechanisms, diagnostic challenges, and why thromboprophylaxis should be tailored rather than routine.

👉 doi.org/10.1016/j.rp...

#Thrombosis #Oncology #CancerResearch
marccarriermd.bsky.social
A new @thrombosiscan.bsky.social survey found that >50% of Canadian cancer patients have little or no awareness of cancer-associated thrombosis (CAT) — a major cause of death in cancer.

📊 Only 27% recalled being educated on CAT risks, yet most want more info!
doi.org/10.1055/a-26...
marccarriermd.bsky.social
☀️ A morning walk, fresh air, and great company – the perfect way to kick off a busy day at #ASHCRTI! 🏃‍♀️💬

Nothing like connecting with colleagues and faculty before diving into a full day of learning. Thanks to everyone who joined us this morning! 🙌

@ash.hematology.org
marccarriermd.bsky.social
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🔍 Key findings:
▪️ Recurrent VTE ruled out without imaging in ~15% of cases (vs >30% in first-time VTE)
▪️ PE suspicion + neg D-dimer = 0/82 recurrent VTE (0%; 95% CI 0.0–4.4)
⚠️ CDRs aren’t foolproof in recurrence.

📄 doi.org/10.1016/j.jt...
@gregoirelegall.bsky.social

🧵👇
marccarriermd.bsky.social
🧵1/
Diagnosing recurrent venous thromboembolism (VTE) is hard.

The international, multicenter PREDICTORS study (n=723) shows that while clinical decision rules (CDRs) still help stratify risk, they’re less effective at ruling out recurrence without imaging.

🩺📉
Reposted by Marc Carrier, MD
rpth.bsky.social
🆕 A new study protocol START aims to investigate the best strategies to reduce risk of thrombosis and thrombocytopenia in cancer patients. @marccarriermd.bsky.social

👉 Click here to read more about the study design and goals! www.rpthjournal.org/article/S247...
Reposted by Marc Carrier, MD
middeldorps.bsky.social
#ISTH2025
middeldorps.bsky.social
Marc Rodger highlighting the #Highlow study and providing guidance on how to implement the results 👌🏼
marccarriermd.bsky.social
Implementation matters!
A guideline-driven VTE prevention program (Vermont Model) led to ~60% of high-risk cancer patients receiving prophylactic anticoagulation—resulting in a 60% reduction in VTE and 56% reduction in death. #ISTH2025 #VTEprevention 🩸
@marycushmanmd.bsky.social
marccarriermd.bsky.social
Correct. Up to 33,000IU daily (18,000 and 15,000 pre-filled syringes)
marccarriermd.bsky.social
🚨 SPECTACULAR RCT at #ISTH2025!

Although non-inferiority to CTPA wasn’t shown, a negative SPECT V/Q scan led to low 3-month VTE risk—
✅ Supporting the safety of ruling out PE with a SPECT-based algorithm
📸 PE diagnosis rates matched other validated strategies

SPECTacular findings indeed! 🫁💥
marccarriermd.bsky.social
🩸 WaVE Study Alert!
In patients with acute CAT & weight >90kg, weight-based dalteparin (200 IU/kg) appears safe & effective.
🔹 Anti-Xa levels aligned with non-obese patients
🔹 Higher levels seen in those with bleeding

Important data to guide dosing CAT & obesity.
📍Presented by Dr. Wang at #ISTH2025
marccarriermd.bsky.social
📣 ARIVA Trial at #ISTH2025:

🧪 First RCT on antithrombotic therapy post-venous stenting for PTS
🔵 6-month primary patency rate was higher than expected
💊 No added benefit of aspirin + rivaroxaban vs. rivaroxaban alone

www.ahajournals.org/doi/10.1161/...
marccarriermd.bsky.social
📢 Long-term results from the CELEST trial presented at #ISTH2025:

🧦 No difference in burdensome PTS (~10%) between 25 vs. 35 mmHg ECS after proximal DVT.
✅ Compliance (>50% use) significantly lowers risk.
🔁 Findings reinforce 2-year RCT data.
📌 A placebo-controlled RCT is still needed.
marccarriermd.bsky.social
Great provocative SOA by Dr. Eikeilboom: are there settings where warfarin outperforms DOACs in AF?💊

Emerging data suggest lower mortality & better overall clinical benefit in AF with obesity or rheumatic disease, possibly via GAS6 inhibition
#ISTH2025 #AF #Thrombosis
marccarriermd.bsky.social
🩸 Important findings from Dr @IMYanXu at #ISTH2025:
Black individuals on extended anticoagulation for secondary VTE prevention had higher rates of major bleeding, including ICH, than White individuals.

🔎 No difference in CRNMB.
📢 Calls for action to address racial disparities.
marccarriermd.bsky.social
🧠 #ISTH2025 SCC survey on stroke in cancer patients:

1️⃣ Physicians choose reperfusion strategies differently for patients with vs. without cancer
2️⃣ Antiplatelets remain the most used for secondary prevention
3️⃣ Major equipoise on workup post-stroke in cancer what is the standard of care?
marccarriermd.bsky.social
🩸 New insights from the RENOVE trial (extended duration anticoagulation) at #ISTH2025:

📉 Reduced-dose DOAC is non-inferior in patients with BMI <30, with less bleeding risk.

⚠️ But in patients with BMI ≥30, reduced-dose may be inferior for bleeding and recurrent VTE.

➡️ Dose matters!
@isth.org
marccarriermd.bsky.social
Meta-analysis on GLP-1RA (vs. placebo) and VTE:
🔹 PE rates significantly lower 📉
🔹 VTE rates lower but not statistically significant
🔹 No difference in DVT
🔹 Study design matters: RCTs vs. observational data
Accepted for publication in JTH!
#ISTH2025 #VTE #GLP1RA #Thrombosis
@jthjournal.bsky.social
marccarriermd.bsky.social
Come say hello to David Airdrie, our Executive Director at Thrombosis Canada, at Booth 623! 👋
Learn more about our clinical guides, patient resources, and upcoming education initiatives.
📍 #ISTH2025
We’re here to connect!
#ThrombosisCanada #VTE @thrombosiscan.bsky.social
marccarriermd.bsky.social
📉 GLP-1RA linked to ~25% lower VTE risk vs. other weight-loss meds in a target trial emulation.
⚖️ No difference when compared to bariatric surgery.

Important findings on obesity, meds, and thrombosis risk.
#ISTH2025 #VTE #GLP1RA
marccarriermd.bsky.social
Recurrent VTE. Away and came back
marccarriermd.bsky.social
📢 Adjust-DVT delivers practice-changing evidence!
Age-adjusted D-dimer safely rules out DVT in patients with low or non-high pretest probability—reducing the need for ultrasounds.
✅ +17% yield in patients ≥75 years
#ISTH2025 #DVT #Thrombosis #VTE