2) This program is intended for #HCPs & is supported by an unrestricted educational grant from Bristol Myers Squibb. Statement of accreditation and faculty disclosures at https://t.co/gvXca4G9Xm.
— cardio-met (@cardiomet_CE) July 5, 2023
FOLLOW US for expert-authored #cardiometabolic programs for 🆓CE/#CME
3b)
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 When dealing with a complication of potential #HCM (stroke or SE, arrhythmia, sudden cardiac death #SCD)
🫀 When evaluating a relative from a case with HCM
🫀 When detecting ECG or echo signs of #LVH, particularly with Q waves or repolarization abnormalities
5a) What is the cause of HCM ?
— cardio-met (@cardiomet_CE) July 5, 2023
It is a disease of the #sarcomere, the basic contractile unit of the myocardial fiber. pic.twitter.com/VRZWNZclei
6) Diagnostic pitfalls
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 False tendons mimicking septal LVH
🫀 Subaortic membrane creating obstruction
🫀 Antero basal or apical hypertrophy may be missed by TTE; contrast TTE can help
🫀 Athlete’s heart can mimic HCM
When in doubt, #strain on #TTE and #MRI can be very useful
7b) Obstruction
— cardio-met (@cardiomet_CE) July 5, 2023
Triggers:
🫀 exertion (stress or exercise echo using a bicycle or a treadmill) or post exertion
🫀 #Valsalva maneuver (may be used when stress echo is not feasible or when there is concern with comorbidities). Typically will trigger lower gradients than exercise.
7d) More on obstruction predicts functional impairment:
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 30% of pts have no obstruction or < 30 mm Hg, NYHA class III/IV = 1.6%
🫀 35% of pts have obstruction > 30 provoked, NYHA class III/IV = 3.2%
🫀 35% of pts have obstruction at rest, NYHA class III/IV = 7.4%
(Maron 2022) pic.twitter.com/TzG4uiBljA
7f) Consequences of obstruction
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 Mitral regurgitation
🫀 LV relaxation impairment, resulting in enlargement of the left atrium and the risk for atrial #arrhythmia
🫀 Reduction of #LV stroke volume
8b) Common symptoms include
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 #Dyspnea
🫀 Chest pain
🫀 #Palpitations
🫀 #Syncope
🫀 Fatigue
🔓 https://t.co/RglMNfeXtx
8d) #EKG abnormalities are common (90% of cases) but nonspecific . . . may see
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 ST-T waves changes
🫀 Deep Q waves
🫀 #LVH
9a) #Echocardiography should
— cardio-met (@cardiomet_CE) July 5, 2023
1. establish #hypertrophy (and in all myocardial segments as #LVH can be localized to any segment) with additional apical views, describing maximal wall thickness, pattern severity, & distribution of hypertrophy
9c) The use of ultrasound enhancing agents can aid in the detection of apical #LVH, #aneurysm, & thrombus in cases where LV apex is suboptimally visualized
— cardio-met (@cardiomet_CE) July 5, 2023
🔓https://t.co/Rjq6llrI2r
🔑 In all cases that remain uncertain or difficult, #CMR should be performed
9e) More #Echocardiography
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 should show #LVOTO if present; if resting gradient is < 50 mmHg, upon provocation (Valsalva or more effectively with effort)
🫀 #SAM
🫀 Secondary MR
10a) Screening for #HCM
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 Subclinical forms, esp during cascade screening, can have milder abnormalities
🫀 Phenotype can vary enormously, even within a given family & over time in a given individual. In a given family, there is also variable #penetrance.
11a) New #imaging methods such as Diffusion Tensor Imaging can be useful to identify cardiomyocyte disarray in hypertrophied and even non hypertrophied segments.
— cardio-met (@cardiomet_CE) July 5, 2023
🔓 https://t.co/fOdqUbmUoc
🔓 https://t.co/L7c7U1PvwP pic.twitter.com/7bpD0djcWm
12) Because of prevalence of #HCM #phenocopies, #DDx should always include non-sarcomeric causes of #LVH, eg:
— cardio-met (@cardiomet_CE) July 5, 2023
🫀 Hypertension
🫀 Aortic stenosis
🫀 Cardiac #amyloid
🫀 Fabry dz
🫀 Mitochondrial cardiomyopathy
All HCM pts should undergo #CMR at least once at the time of diagnosis
14a) So, about #SCD in #HCM:
— cardio-met (@cardiomet_CE) July 5, 2023
Sudden Cardiac Death
🧮#Risk assessment for #SCD required in all patients
🫀 #RF for SCD may differ in weight among children vs adults, & problems & complications of #ICDs also differ
🫀 Risk of SCD is approximately 1% per year in adults
14c) (cont)
— cardio-met (@cardiomet_CE) July 5, 2023
1⃣ #SCD judged definitively/likely attributable to #HCM in ≥1 first-degree or close relatives ≤50 years of age
2⃣ Massive #LVH ≥30 mm in any LV segment
14e) (cont)
— cardio-met (@cardiomet_CE) July 5, 2023
6⃣ Extensive LGE on CMR
7⃣ #NSVT on Holter pic.twitter.com/glUwDXCHRM
14g) Free web calculator for @escardio score at https://t.co/ZJvgcOjauR
— cardio-met (@cardiomet_CE) July 5, 2023
or
get out your calculator: pic.twitter.com/BDUBai9F2C
15a) Let's pause and do a quick knowledge ✔️.
— cardio-met (@cardiomet_CE) July 5, 2023
Which of the following is NOT a major #riskfactor for #SCD in the #ACC/#AHA #HCM guidelines?
a. Massive #LVH ≥30 mm in any LV segment
b. LV systolic dysfunction (EF<50%)
c. #atrialfibrillation
d. #NSVT on Holter
16a) WELCOME BACK! We are talking both general & (interventional #cardiology) specialty foundational knowledge re #HCM. Our expert author is @gabrielsteg & you are earning 🆓 CE/#CME by following this 🧵.
— cardio-met (@cardiomet_CE) July 6, 2023
Did you answer the quiz in tweet 15a? If not, scroll back ⤴️ & do it now!
17) General lifestyle measures for pts with #HCM and obstruction
— cardio-met (@cardiomet_CE) July 6, 2023
🫀 Avoid dehydration & alcohol
🫀 Avoid heavy meals
🫀 Have regular low to moderate level physical activity
🫀 Consider losing weight
🫀 Avoid #diuretics & #vasodilators
🫀 In case of #AFib, avoid #digoxin
18a) Medical Management
— cardio-met (@cardiomet_CE) July 6, 2023
🫀 #Beta_Blockers
For symptomatic obstruction, non-vasodilator #BBs should be titrated to max tolerated dose (grade IB)
This will help control symptoms in ~ 2/3 of cases
Side effects including fatigue, bradycardia, hypotension, erectile dysfunction.
18c) Calcium channel blockers #CCBs
— cardio-met (@cardiomet_CE) July 6, 2023
Alternative to #BB in intolerant pts. Start #verapamil at 40mg tid, can titrate up to 480 mg/d but caution if gradient > 100 mmHg or w/#PH due to the risk of pulmonary edema.
19a) 🔑points:
— cardio-met (@cardiomet_CE) July 6, 2023
👉In asx pts, even when a gradient at rest, evidence medical Rx will improve outcomes.
👉#Heartfailure sx in pts without #LVOTO should be treated like all #HFrREF pts
19c) #LVEF <50% connotes significantly impaired systolic function and identifies individuals with poor prognosis and who are at increased risk for #SCD
— cardio-met (@cardiomet_CE) July 6, 2023
21a) Septal reduction therapies #SRT (#myectomy or alcohol septal ablation #ASA) by an experienced operator can be considered in pts with drug refractory or severe #LVOTO causing sx or signs of decompensation or symptoms
— cardio-met (@cardiomet_CE) July 6, 2023
21c) #ASA creates a “controlled” MI & therefore has the potential comps of a large MI, inc ventricular tachyarrhythmias, LV dysfunction
— cardio-met (@cardiomet_CE) July 6, 2023
🔑SRT should not be performed in asymptomatic pts with normal exercise capacity
21e) #SRT in #centersofexcellence appears to be associated, at least in selected series, with excellent #survival, matching that of the general population.
— cardio-met (@cardiomet_CE) July 6, 2023
See 🔓 https://t.co/ZTXl5LDj2l pic.twitter.com/QEzZ37iq8J
22a) Atrial Fibrillation in #HCM
— cardio-met (@cardiomet_CE) July 6, 2023
🫀 #AFib is 6 X more common in HCM than in the general population. It may be possible to predict the occurrence of AFib in HCM based on left atrial size. A point-based risk score has been developed 🔓 https://t.co/h48R4X34Fr
22c) However, outcomes of #HCM patients with #Afib have substantially improved in the past 20 years ( 🔓 https://t.co/0k1IqzIIz0 ) & Afib is no longer an independent predictor of death in HCM (🔓 https://t.co/08ECus0FQJ).
— cardio-met (@cardiomet_CE) July 6, 2023
22e) When #HCM pts develop #AFib, their #embolic risk is high and all are candidates for long term oral anticoagulation, irrespective of CHA2DS2VASc score, which in fact is unreliable in HCM.
— cardio-met (@cardiomet_CE) July 6, 2023
22g) Direct oral anticoagulants #DOACs are recommended as first line anticoagulant therapy over Vitamin K antagonists #VKA (ACC/AHA guideline grade 1)
— cardio-met (@cardiomet_CE) July 6, 2023
23b) Recreational exercise
— cardio-met (@cardiomet_CE) July 6, 2023
For most pts w/#HCM, mild- to moderate-intensity recreational exercise is beneficial to ⬆️🫀🫁 fitness, physical functioning, & quality of life, & for their overall health in keeping with physical activity guidelines for the general population
23d) areas of debate
— cardio-met (@cardiomet_CE) July 6, 2023
For pts with #HCM, participation in high-intensity recreational activities or moderate- to high-intensity competitive sports activities may be considered after a comprehensive evaluation and shared discussion . . .
23f) … for competitive sports participation often involve third parties (e.g., team physicians, consultants, and other institutional leadership) acting on behalf of the schools or teams (grade 2b, ACC/AHA).
— cardio-met (@cardiomet_CE) July 6, 2023
24a) What about the novel therapies? Myosin inhibitors#Mavacamten is a #myosin inhibitor, which can be used (generally as a second line therapy in addition to beta blockers or calcium channel blockers, although it has been used alone) to improve symptoms of #HCM.
— cardio-met (@cardiomet_CE) July 6, 2023
24c) … shown to improve exercise capacity as measured from #CPX & decreased #LVOT gradients, & decrease biomarkers such as #natriuretic peptides or #troponin. Learn more from prior #tweetorials in our series https://t.co/7KtfmhxiaX pic.twitter.com/BOPHszdjgf
— cardio-met (@cardiomet_CE) July 6, 2023
24e) Tolerance of mavacamten
— cardio-met (@cardiomet_CE) July 6, 2023
It is generally well tolerated but requires careful monitoring of #LV systolic function by TTE in order to detect decreases in #LVEF.
24g) Effect on LVH
— cardio-met (@cardiomet_CE) July 6, 2023
Echo has shown that #mavacamten treatment not only reduces the #LVOTO gradient, but also reduces LV #hypertrophy & improves diastolic function.
25a) #Mavacamten was @US_FDA approved in 🇺🇸 in 2022 for symptomatic #HOCM starting at 5 mg OD with uptitration to 15 mg OD, based on EXPLORER HCM and VALOR
— cardio-met (@cardiomet_CE) July 6, 2023
25c) The future?
— cardio-met (@cardiomet_CE) July 6, 2023
🫀 Mavacamten is also currently being studied in non-obstructive hypertrophic cardiomyopathy in the #MAVERICK_HCM trial
🫀 Other #myosin inhibitors such as #aficamten are currently being tested in clinical trials pic.twitter.com/jvE99N0F1c
27) WELCOME BACK to the conclusion of this comprehensive review of #hypertrophic #cardiomyopathy, led by @gabrielsteg and providing YOU with 1⃣ hour 🆓CE/#CME without ever having to leave Twitter!#CardioTwitter #CardioEd #FOAMed
— cardio-met (@cardiomet_CE) July 7, 2023
28b)
— cardio-met (@cardiomet_CE) July 7, 2023
🫀 Assess symptom burden: since benefit is mostly symptomatic, the procedure should be restricted to pts who remain clearly symptomatic despite optimized medical Rx
28d)
— cardio-met (@cardiomet_CE) July 7, 2023
🫀 Basal septum thickness should be ≥15 mm (to reduce risk of #VSD). @escardio guidelines rec ≥ 17 mm
🫀 Rule out subaortic band or mitral valve abnormalities req'ing surg
🫀 Given that RBBB occurs in majority of ASA pts, LBBB means high probability for permanent pacing
30a) The ASA Procedure
— cardio-met (@cardiomet_CE) July 7, 2023
🔓 https://t.co/VyeD2pU698
🔓 https://t.co/W3mGjR1s7v
🔓https://t.co/QBjjLbsFoF pic.twitter.com/oDkuaWiT74
30c) Selectively #catheterize the left coronary artery #LCA and then place a wire and #OTW balloon in the target #septal branch. Once the balloon is inflated, this creates a secure environment for septal injection and the guidewire can be removed.
— cardio-met (@cardiomet_CE) July 7, 2023
31b) … to ensure that the myocardial area supplied by the septal branch includes the area of #SAM contact. If contrast is observed elsewhere, an alternative septal branch should be sought
— cardio-met (@cardiomet_CE) July 7, 2023
31d) Alas, up to 15% of patients have no suitable septal branch that supplies #perfusion to the septal area of contact with #SAM pic.twitter.com/LqM048Klhd
— cardio-met (@cardiomet_CE) July 7, 2023
32b) A small amount of contrast (0.5 ml) should be injected via the #OTW catheter to check with fluoroscopy the lack of spillback of contrast and lack of connection with other major coronary vessels.
— cardio-met (@cardiomet_CE) July 7, 2023
33a) Once the target artery has been identified and secure injection verified, a small volume of 96% ethanol (1 to 3 ml ) should be given in small increments, under #conscious_sedation, as the injection can be painful
— cardio-met (@cardiomet_CE) July 7, 2023
33c) An alternative method is to give repeated slow injections of 0.5 ml with #echocardiographic and #hemodynamic evaluation after each injection. This stepwise method allows stopping as soon as the expected hemodynamic effect is reached
— cardio-met (@cardiomet_CE) July 7, 2023
33e) There is an immediate reduction of #LVOT obstruction. The goal should be a reduction of 50% or more. It is recommended to assess obstruction post #VPB, which should be reduced by at least 50%. VPBs can be triggered by the pigtail in the #LV. pic.twitter.com/eRgpP7yAwF
— cardio-met (@cardiomet_CE) July 7, 2023
34a) Here’s an example of a successful #ASA : pic.twitter.com/lbXCO8Ggll
— cardio-met (@cardiomet_CE) July 7, 2023
35) Time course of changes in obstruction
— cardio-met (@cardiomet_CE) July 7, 2023
The initial ⬇️ in gradient can be followed by a transient ⬆️in pressure gradient in the 1st week, then subsequent ⬇️ of #LVOT obstruction in the following months, caused by remodeling of the ablated septum. 🔓 https://t.co/bIKI5lBS1r
36b)
— cardio-met (@cardiomet_CE) July 7, 2023
🫀 Hospital monitoring of 5-6 days is recommended.
🫀 If pacing is required for more than 48 h, consider permanent pacing.
36d)
— cardio-met (@cardiomet_CE) July 7, 2023
🫀 Monitoring CK and #troponin release can be useful as it is correlated to the result of #ASA.
37b) The answer is b, #LBBB, because #ASA is likely to induce a #RBBB.
— cardio-met (@cardiomet_CE) July 7, 2023
37c) The answer is #Afib, which is a common comorbidity (and complication) of #HCM, but isn’t in the risk score. The components are:
— cardio-met (@cardiomet_CE) July 7, 2023
o Age
o Max wall thickness
o Max #LVOT gradient
o Left atrial diameter
o Family hx of #ICD
o Hx of unexplained #syncope
o Hx of #NSVT
38) Great job! You just earned 🆓 1.0hr CE/#CME! Go to https://t.co/qV5P62Supq and claim your certificate! .@gabrielsteg & @cardiomet_ce thank you for joining us. Follow us for more #MedEd!
— cardio-met (@cardiomet_CE) July 7, 2023