Matt Daniels MD PhD

@wi_john @nytimes If clinical academics were a species we would be on an endangered list, and very high up it.

@wi_john Correct!

“Early-career researchers are the first to absorb funding uncertainty and are internationally mobile. Given the cuts to PPAN science, the very people who the minister claims to want to retain are leaving the country.” theguardian.com/technology/202…

A nail biting few moments while we wait for CHAMPION-AF to be presented at #ACC2026. The audience here shows equipoise ⬇️

@benhibbertMDPhD @DFCapodanno In some parts of the world discussion may be needed, after all if they want to pay for a mechanical solution over a tablet - Why not? In other parts of the world, a 77yo cohort with a 5% annual mortality may default to lower cost less invasive option if/when there's equipoise

@cardiacpolymath @DFCapodanno Patient preference. Agree to say you need to have laac it will need to be superior in terms of bleeding reduction and equivalent in stroke. But they may show that. If it’s a clear win on bleeding you at least need to discuss it with your patient.

All the explanations I’ve heard today for the negative CLOSURE-AF result—some so strained they’re almost impressive. 1) The devices were “outdated” and therefore responsible for excess complications (the usual argument that things only go wrong elsewhere). 2) DAPT was used after LAAO, which is now said to be obsolete because of bleeding concerns compared with DOAC-based strategies (a claim that is often repeated, less often demonstrated). 3) Stroke rates were similar, so the signal is attributed mainly to bleeding and procedural issues—as if that were a minor point. 4) The composite endpoint is criticized for mixing different mechanisms, although if anything it should have favored non-inferiority. 5) The early phase of enrollment is invoked to argue that complications are not representative of current practice (again, complications seem to belong to others). 6) And then there are the usual remarks about loss to follow-up, crossovers, and lack of blinding. What seems to be missed in this accumulation of arguments is straightforward: the burden of proof lies with LAAO, not with the control arm. The issue is the strength of the evidence supporting LAAO, not medical therapy, which remains the reference standard.

@TaiebPhil How do you get periprocedure mortality at 1.2%? I've seen 2 deaths out of 400+ implant attempts in the paper <0.5% mortality very similar to other recent studies What have I got wrong?

Here are my reservations on the CLOSURE-AF findings: I would have no difficulty accepting a trial showing that LAAO is inferior to medical therapy. But if a trial fails, the reason for that failure should make clinical sense — whether due to lower efficacy for stroke prevention or a lack of meaningful bleeding reduction. What I struggle with is the reflex to blindly accept evidence uncritically when it appears to contradict clinical logic so directly. A few points stand out: 1. The medical arm does not reflect true high-bleeding-risk practice. More than 85% of patients in the medical therapy arm were treated with DOACs or even more intensive antithrombotic regimens. That is difficult to reconcile with the population the trial is supposed to represent: patients at truly high bleeding risk or with contraindications to anticoagulation. Are we really supposed to believe that this group experienced fewer bleeding events than patients in the device arm, most of whom were on SAPT or no antithrombotic therapy after 3–6 months? 2. Crossover was substantial. Thirty-two patients crossed over to the medical arm, representing about 7% of the trial population. That is not trivial and complicates interpretation. 3. Procedural safety was unexpectedly poor. A periprocedural complication rate of 6.2% is strikingly high — more than 3 to 4 times higher than what has been reported in contemporary practice, including SURPASS (~1.3%) and even randomized data such as Amulet IDE. A periprocedural mortality rate of 1.2% is frankly alarming. For so-called expert centers, this is difficult to ignore. The 4.3% rate of periprocedural bleeding is also difficult to accept as representative of modern LAAO practice. In experienced hands, venous access with a 12–14 Fr sheath — especially when closed with ProGlide or even a figure-of-8 stitch — should rarely lead to clinically significant bleeding in patients who are not anticoagulated. It is also notable that no meaningful subanalysis was presented by device type, despite prior signals suggesting differences in procedural safety between platforms. 4. The bleeding signal may actually favor LAAO over time. Bleeding beyond 3–6 months was lower in the device arm than in the medical arm. That is exactly what one would expect biologically. LAAO exchanges an upfront procedural risk for a lower cumulative long-term bleeding burden. If so, the benefit should become more apparent with longer follow-up and the benefits might still appear after longer follow-up. In addition, this makes the loss to follow-up particularly important. As roughly 25% of patients were lost to follow-up after the first 6 months, that creates a meaningful bias against demonstrating the long-term advantage of LAAO. 5. The excess in cardiovascular death also raises mechanistic questions. The device arm showed more cardiac arrests and more MIs. But what is the plausible mechanism? A device-related embolic explanation seems unlikely given that ischemic stroke rates were similar between groups, and strokes account for the vast majority of AF-related systemic embolic events. A more plausible explanation would be procedural factors — air embolism, tamponade, thromboembolism — but if that is the case, then the issue is again procedural quality, not a true indictment of the LAAO strategy itself. I am very interested to see the results of CHAMPION-AF. This may end up being a situation similar to COAPT vs MITRA-FR: same concept, very different trial signals, and a very different interpretation once the dust settles. When data contradict common sense, the answer is not to abandon common sense immediately — it is to examine the data more carefully. #Cardiology #CardioTwitter #EPeeps #Afib #LAAO #StrokePrevention #ClinicalTrials #MedTwitter #StructuralHeart @NEJM @DFCapodanno @drjohnm @AsherElad @escardio

@benhibbertMDPhD @DFCapodanno I'm not sure what CHAMPION or CATALYST may show, but I do think to change practice a superiority result is needed Even if there was equivalence (which CLOSURE-AF disputes) the health economic argument for a $10's K device procedure Vs a DOAC portfolio about to come off patent =?

I actually think it’s super impressive laac and drug are equal. Procedural adverse events (ie device selection and implanted ability) are major drivers of bleeding events which drove the endpoint. 4% of patients got transfused. So if you can do it safer and not increase bleeding it’s a win for laac. Wait and see event rates in Champion - they will reflect what we do today. Closure shows laac is now as safe as drugs for stroke - as we continue to improve safety (champion/catalyst) laac will be superior.

@wi_john @nytimes Good, now address the state medical license process

Bipartisan Bill Would Waive $100,000 Visa Fees for Medical Professionals “The bill, sponsored by two Republicans and two Democrats in the House, seeks to alleviate shortages of doctors and nurses in the U.S.” nytimes.com/2026/03/17/us/… via @NYTimes

@bogdienache @drjohnm What do you think the AF attributable risk of stroke is in a CHADSVASC score of 5.2? Is prediction 5 coming true? interventional.theclinics.com/article/S2211-…

NOT NOINFERIOR and INFERIOR

@NatRevCardiol @StructuralBCN Holy grail if it works in patients Anatomy agnostic closure system that can be delivered through an angiography catheter Systemic embolism has been the Achilles heel for variations on this theme

New online! Injectable magnetofluid achieves complete, thrombus-free LAA occlusion in preclinical models dlvr.it/TRY4kV

@TorBiering @dan_atar @CTCPR_ @RigsHeart The aeroplanes are full of Scandi cards at least

Meeting Scandinavian Cardiologists all over the world! Yesterday I met professor Finn Gustafsson (who lives in SF and not DK) in London and today I met professor @dan_atar on the plane to Tokyo. The world is small and full of Scandinavian Cardiologists @CTCPR_ @RigsHeart

Welcome to our March 18 issue of #JACCCaseReports @JACCJournals. jacc.org/journal/case-r… Full PDF here: jacc.org/doi/10.1016/S2… @MinnowWalsh @hmkyale @Justine_Turco Coronary, Peripheral and Structural Interventions: Complete or Partial Revascularization During Emergency PCI in a Patient With NSTEMI jacc.org/doi/10.1016/j.… Recurrent Transient Cortical Blindness After Bilateral Carotid Artery Stenting jacc.org/doi/10.1016/j.… Novel Approach Using Aspiration Thrombectomy for Aortic Root Thrombus After LVAD Implantation jacc.org/doi/10.1016/j.… Aortic Root Thrombosis in LVAD Patients: An Underrecognized Problem With Evolving Management jacc.org/doi/10.1016/j.… Pulsed-Field Ablation With Transcatheter Left Atrial Appendage Occlusion for Left Atrial Appendage–Origin Atrial Tachycardia jacc.org/doi/10.1016/j.… Rhythm Disorders and Electrophysiology: Concomitant Pulse Field Ablation Based LAA Isolation Plus LAAC jacc.org/doi/10.1016/j.… Coronary, Peripheral and Structural Interventions: Extension Catheter-Assisted Balloon Anchoring Technique for Retrieval of an Entrapped Balloon Catheter During PCI jacc.org/doi/10.1016/j.… Late Hybrid Retrieval of an Embolized Left Atrial Appendage Occlusion Device: A Case and Literature Review jacc.org/doi/10.1016/j.… Digital Ischemia Following Radial Access Unmasking Systemic Sclerosis: Characteristic Intravascular Ultrasound Findings jacc.org/doi/10.1016/j.… Guidewire Entry Into a Calcific Fracture Causing Stent Underexpansion: A Pitfall of Intravascular Lithotripsy jacc.org/doi/10.1016/j.… ICE-Guided Percutaneous Thrombectomy of Thrombus-in-Transit With Impending Paradoxical Embolism Through PFO and Pulmonary Embolism jacc.org/doi/10.1016/j.… ICE-Guided Percutaneous Thrombectomy of Thrombus-in-Transit and PE jacc.org/doi/10.1016/j.… Patient-Specific 3D Coronary Reconstruction and Computational Simulations to Guide Drug-Coated Balloon Intervention: First-in-Human Experience jacc.org/doi/10.1016/j.… Rhythm Disorders and Electrophysiology: Pulsed-Field Redo Ablation With Balloon Angioplasty for Postablation Pulmonary Vein Stenosis jacc.org/doi/10.1016/j.… Pulsed-Field Ablation With a Persistent Left Superior Vena Cava: Potential for Transmural Ablation jacc.org/doi/10.1016/j.… Pulsed Field Ablation’s Collateral Effects on Persistent Left Superior Vena Cava: Durable or Temporary Electroporation? jacc.org/doi/10.1016/j.… REM Sleep-Associated Asystole jacc.org/doi/10.1016/j.… Successful Everolimus Therapy for Atrioventricular Block Due to Cardiac Rhabdomyoma Associated With Tuberous Sclerosis Complex jacc.org/doi/10.1016/j.… Biatrial Macroreentrant Tachycardia Involving Persistent Left Superior Vena Cava and Bachmann’s Bundle jacc.org/doi/10.1016/j.… The Electrophysiologist's Worst-Case Scenario: Aortic Near-Miss Revealed by Contrast-Enabled Radiofrequency Needle jacc.org/doi/10.1016/j.… Imaging: Cardiac Hydatid Cyst: A Diagnostic and Therapeutic Challenge Requiring a Multidisciplinary Approach jacc.org/doi/10.1016/j.… Takayasu Arteritis Presenting With Cardiac Arrest: An Intravascular Imaging Triggered Diagnosis jacc.org/doi/10.1016/j.… Pentalogy of Cantrell: Comprehensive Multimodal Imaging Evaluation in an Adult With Ectopia Cordis jacc.org/doi/10.1016/j.… Epicardial Fat Necrosis Leading to Constrictive Pericarditis: Missed Diagnosis and Subsequent Resolution jacc.org/doi/10.1016/j.… “Burned-Out” Hypertrophic Cardiomyopathy: Overlap on Cardiac MRI With Other Nonischemic Cardiomyopathies jacc.org/doi/10.1016/j.… Squat in Obstructive Hypertrophic Cardiomyopathy jacc.org/doi/10.1016/j.… Cardio-Oncology: Life-Threatening Cardiogenic Shock During Chemotherapy: The Role of Mechanical Ventricular Support in Cardio-Oncology Patients jacc.org/doi/10.1016/j.… Chemotherapy as Second Hit in Desmoplakin Cardiomyopathy jacc.org/doi/10.1016/j.… Second Hits Are Common Drivers of Genetic Heart Disease jacc.org/doi/10.1016/j.… Congenital Heart Disease: Bilateral Epicardial Coronary Microfistulas With Anomalous Deviation jacc.org/doi/10.1016/j.… Transcatheter Occlusion of Hepatic Vein–Atrial Communication After Modified Fontan in a Child Post Kawashima Surgery jacc.org/doi/10.1016/j.… Strengthening Education for Advanced Practice Providers in Adult Congenital Heart Disease Care jacc.org/doi/10.1016/j.… Heart Failure and Cardiomyopathies: Gene Testing Across Phenotypes of Hypertrophic Cardiomyopathy jacc.org/doi/10.1016/j.… Danon Disease Diagnosed by Multimodal Imaging jacc.org/doi/10.1016/j.… Valvular Heart Disease: Strategic Reintervention With Marked Oversizing and Overexpansion in TAV-in-SAV for Hemolytic Paravalvular Leak jacc.org/doi/10.1016/j.… Decellularized Pulmonary Homograft Repair of Idiopathic Main Pulmonary Artery Aneurysm in SC Hemoglobinopathy jacc.org/doi/10.1016/j.… Vascular Medicine: Chronic Bilateral Distal Radial and Ulnar Artery Occlusion Presenting as Peripheral Neuropathy in a Young Adult jacc.org/doi/10.1016/j.… A Rare Large-Artery Complication of Cryoglobulinemia: Superior Gluteal Artery Pseudoaneurysm jacc.org/doi/10.1016/j.… Genetics, Omics and Tissue Regeneration: Achilles Tendon Xanthoma Inflammation Revealed by FDG-PET/CT in Familial Hypercholesterolemia: Insights From a 2-Generation Case Series jacc.org/doi/10.1016/j.… FDG-PET/CT of Achilles Tendon Xanthoma: A Hot Take on Imaging in Familial Hypercholesterolemia jacc.org/doi/10.1016/j.… Cardiometabolic: Myocardial Ischemia in Young Women With Familial Hypercholesterolemia: Similar Presentation and Divergent Treatment Response jacc.org/doi/10.1016/j.… Consequences of Late Diagnosis and Insufficient Cholesterol Treatment in Women With Heterozygous Familial Hypercholesterolemia jacc.org/doi/10.1016/j.… Hypertension: Malignant Hypertension and Torsades De Pointes as Initial Presentations of Primary Aldosteronism jacc.org/doi/10.1016/j.… Surgery: Simultaneous TAVR and EVAR for Severe Aortic Regurgitation With Giant Abdominal Aortic Aneurysm jacc.org/doi/10.1016/j.… Critical Care and Resuscitation: Over-the-Counter Loperamide Overdose Resulting in Cardiac Arrest jacc.org/doi/10.1016/j.… @aronisMD @JACabreraCardio @MiChen__ @aabha_divya @sarano_maurice @Miho_Fukui_ @ErikaHuttce @Nishaki1 @ChrissyMD2000 @ACHDocTMoe @M_Pompeu_Sa_MD @jsaef1 @JTSaxon @AndreaScotti21 @Kentso987 @TagliariPaula @m_taramasso @SyedZaidMD Author’s handles: @AhmedKazemDO @SamSayfo @DaliaTarun @ChristianHeeger @icruzgonzalez @nakatamarohito @AlexLee @kentso987 @LaiLeoDr @tan_guangming @YChatzizisis @WongChrisX @ftrae @JessHuangMD @ScrippsCVFellow @NiloofarJavadi @AJamilTajik @BURZOTTA_F @sdelcastillo84 @shantellebart88 @abavishi23 @mmartinezheart @enta_yusuke @Reynardls @rauldsf_santos @jianfangluo

@gbiondizoccai @willsuh76 @NEJM Its probably not so clear-cut to end LAAc completely But likely is meaningful in terms of shifting the group think on the target patient population that might benefit & what it can deliver Chadsvasc is full of athero risk factors, this trial had 5.2, LAAc isn't a magic wand

A deathly blow to left atrial appendage closure (LAAC)? In the CLOSURE-AF trial including 912 patients with AF at high risk for stroke and bleeding, LAAC was significantly worse than DOAC or other medical Rx nejm.org/doi/full/10.10… @NEJM

@DFCapodanno @NEJM Will it be another Mitra-fr & coapt situation? Nice buildup to the ACC session next week

Perfect timing—and a bit of a cruel twist, one might say. In a week, CHAMPION-AF may tell a different story, but the long-awaited CLOSURE-AF, now out in @NEJM, makes for a tough week ahead for those supporting left atrial appendage closure. nejm.org/doi/full/10.10…

@euanashley Voice recognition technology for the Scottish accent A classic from 2010 youtu.be/NMS2VnDveP8

In my continuing series.

@djc795 @drjohnm @AndrewFoy82 @MRuzieh I agree with @drjohnm on the principle that procedural complications like bleeding shouldn't be swept under the carpet It's true that the cause is different than bleeding in follow-up - because there's a hole in a vessel & heparin with a team ready to manage it - but fairs fair

@drjohnm @AndrewFoy82 @MRuzieh Totally agree— esp with B and C. We often underestimate the bleeding risk of even SAPT in elderly pts. And Apixiban is a damn good OAC.

> 600,000 left atrial appendage devices have been placed NOT NONINFERIOR 👇🏻 Trial is large, nonindustry funded and done in experienced centers in Germany Endpoint had both efficacy and safety components and still did not make non-inferiority I tried to tell you all

@shaun37273736 @djc795 @drjohnm @AndrewFoy82 @MRuzieh For 446 implants those numbers aren't bad

@djc795 @drjohnm @AndrewFoy82 @MRuzieh Need better operators with lower procedural complications and more experience! Insane complication rates! periprocedural complications within 7 days: 5.7% •18 major bleeds •5 tamponades •1 device embolization requiring surgery •2 deaths within 7 days.

@drjohnm Look forward to it Will we see a mitra-fr & coapt pattern repeat Or will there be two negative outcomes? Place bets now

Tomorrow I will have expanded coverage on the This Week in Cardiology (TWIC) podcast of CLOSURE, as well as some context for the upcoming CHAMPION trial to be presented at #ACC26 It will be crucial to be fully informed on CHAMPION's design before the results are presented

I am Sam Hazen, CEO of HCA Healthcare. The largest for-profit hospital system in the United States. One hundred and eighty-two hospitals. Twenty states. I oversee a spreadsheet called the chargemaster. It has 42,000 line items. Each line item is a price. The prices are not real. I need to be precise about that. They are not estimates. Not approximations. Not market rates. They are anchors. An anchor is a number you set high so that every negotiated discount feels like a victory. No relationship to cost. No relationship to value. A relationship to leverage. My team sets the anchors. That is the job. The price is correct. Take a drug. Keytruda. Immunotherapy. Treats sixteen types of cancer. The manufacturer charges approximately $11,000 per dose. That is the acquisition cost. What the hospital pays. My team enters it into the chargemaster. They do not enter $11,000. They enter $43,000. That is the gross charge. The gross charge is a fiction. No one pays it. No one is expected to pay it. The gross charge exists so that when Blue Cross negotiates a 68% discount, they pay $13,760, and the contract says "68% discount" and both parties feel the transaction was rigorous. A 68% discount on a fictional price produces a real price that is 25% above acquisition cost. That margin is where I live. My 2025 compensation was $26.5 million. Eighty percent of my bonus is tied to EBITDA. Earnings Before Interest, Taxes, Depreciation, and Amortization. It is also earnings before the patient opens the bill. Same dose of Keytruda at the hospital across town. Gross charge: $12,000. Blue Cross rate: $10,200. Same drug. Same dose. Same needle. Same cancer. Different spreadsheet. The CMS transparency data showed the ratio between the highest and lowest negotiated price for the same drug at the same hospital can reach 2,347 to one. Not 2x. Not 10x. Not 100x. Two thousand three hundred and forty-seven to one. For the same thing. In the same building. On the same Tuesday. The price is correct. Every drug in the chargemaster has twelve prices. Twelve. Gross charge. Medicare rate. Medicaid rate. Blue Cross. Aetna. Cigna. UnitedHealth. Humana. Workers' comp. Tricare. Auto insurance. And the self-pay rate. The self-pay rate is for the person without insurance. It is the gross charge. The fictional number. The anchor. The person without insurance pays the number that was designed to be negotiated down from. They pay the ceiling because they have no one to negotiate on their behalf. Same drug. Same chair. Same nurse. They pay the price that no insurer in the country would accept. I maintain a file. CDM line item 637-4892-PKB. Saline flush. Sodium chloride 0.9%. Acquisition cost: $0.47. We charge $87. That is an 18,410% markup. The saline flush is used before and after every IV infusion. A chemo patient receiving twelve cycles will be charged $87 for saline fourteen times per visit. I know the math. My team built the math. The math is the job. The price is correct. In 2021, the federal government required hospitals to publish their prices. The Hospital Price Transparency Rule. Machine-readable file. Gross charges. Discounted cash prices. Payer-specific negotiated rates. We complied. We posted the file. The file is a 9,400-row CSV on our website under "Patient Financial Resources." Four clicks from the homepage. Column F: "CDM_GROSS_CHG." Column J: "DERV_PAYERID_NEGRATE." My team designed the column headers. They designed them to comply. They did not design them to communicate. CMS reported 93% of hospitals now post a file. Compliance. But only 62% of the posted data is usable. That gap is where we operate. We are compliant. The data is published. The data is incomprehensible. A researcher downloaded our file. She spent three weeks cleaning it. She called the billing department for clarification on 340 line items. They transferred her four times. The fourth transfer was to a voicemail box that was full. She published her analysis anyway. Cardiac catheterization lab charges: $8,200 to $71,000 for the same procedure depending on the payer. The report received eleven views on our press monitoring dashboard. I saw it. I did not forward it. On April 1, a new CMS rule takes effect. Hospital CEOs must personally attest — by name, encoded in the machine-readable file — that the pricing data is "true, accurate, and complete." My name. Sam Hazen. In the file. Attesting that 42,000 fictional anchors are true, accurate, and complete. They are complete. I will give them that. Forty-two thousand line items is nothing if not complete. A new analyst read the transparency data. She asked why the same MRI costs $450 for Medicare and $4,200 for Aetna in the same building on the same machine. I told her the rates reflect negotiated contractual agreements between the payer and the facility. She said that doesn't explain the difference. I told her the difference IS the contractual agreement. She said that sounds like the price is arbitrary. I told her the price is the result of a rigorous, multi-variable analysis that accounts for acuity, case mix, regional market dynamics, and payer contract terms. She asked if I could show her the analysis. I told her the analysis is proprietary. The analysis does not exist. The analysis is my team, in Q4, adjusting the chargemaster upward by the percentage the CFO wrote on a sticky note. The sticky note this year said "6-8%." They chose 7.4% because it is between six and eight and it has a decimal, which makes it look calculated. She stopped asking. The price is correct. My insurance. The executive health plan. Not in the chargemaster. Administered separately. I do not pay the gross charge. I do not pay the negotiated rate. I pay a $20 copay for services at our own facilities. Gross charge for my treatment: $14,200. Insured rate for our largest commercial payer: $8,600. I pay $20. The executive health plan was designed by the Chief Human Resources Officer and approved by the compensation committee. I was not on the compensation committee. I was a beneficiary of it. That is a different thing. I benefit from the system I price. I price the system I benefit from. These are two separate facts that happen to involve the same person. HCA Healthcare was named the Most Admired Company in our industry by Fortune magazine for the twelfth consecutive year. That was February. The same month I sold $21.5 million in company stock and purchased zero shares. Fortune did not ask about the chargemaster. I am Sam Hazen, CEO of HCA Healthcare. I have 42,000 prices in a spreadsheet across 182 hospitals. None of them are real. All of them are charged. Same drug: $12,000 or $43,000. Depends on which spreadsheet. Which building. Which contract. Which page of which PDF. The patient who has no contract pays the most. The researcher who found the discrepancy got a voicemail box that was full. The analyst who asked why stopped asking. The executive who prices the system pays $20. On April 1, I will personally attest that this is true, accurate, and complete. The price is correct. The price has always been correct. I am the price.

@drjohnm The dysfunction in US clinical research was apparent for all to see during COVID NYC got battered with it (intensity & severity) months before the UK did Academically RECOVERY wasn't complicated - use existing meds & randomisation to find what works Why didn't US do first?

Good. Good. Just so remarkable that our field depends on countries w public health systems to answer these sorts of questions. Too much of US research is industry based which only gets done when there are confluences of interests b/w profit and pt care

@Gasman_J @wesstreeting @IJOA_Journal Would an obstetric physician be a useful participant too ..... Most maternal deaths come from preexisting conditions, mostly those affecting the heart

The absence of an obstetric anaesthetist on this task force is a serious omission, @wesstreeting . @IJOA_Journal