Thread by @realdocdan

🧵 1/8 Myocardial bridging is present when part of coronary artery dips into & underneath heart muscle. Let’s dig deeper. 📖
Educational thread 🧵 1/8
#MedEd #CardioEd #CardioTwitter #MedTwitter #radialfirst @JACCJournals @YoungDgk @DGK_org @AGIKinterv @CardioNerds @escardio

https://twitter.com/steph_achenbach/status/1529886637580333060

📍2/8 Myocardial bridging is a congenital coronary artery anomaly, in which a segment of the artery (tunnel segment) dips into the myocardium (myocardial bridge).

📍3/8 Methods of detection vary greatly in sensitivity.
Myocardial bridging is seen in

🥇30% of pts in autopsy
🥈20% of pts in coronary CT-scan
🥉5% of pts in coronary angiography
#CardioTwitter #MedTwitter #RadialFirst

📍4/8 Presence of symptoms depends on
1) depth: >2 mm tunnel from surface
2) length: >2.5 cm tunnel segment
3) vasospasm
4) sympathetic tone: ⬆️ heart rate & ⬆️ contractility results in ⬇️ coronary perfusion
5) septal branching from bridge: ⬇️ perfusion due to Venturi effect

📍5/8 Epidemiology: compared to average CAD collective typical pts w/ myocardial bridging seem to be

1) younger
2) smoker (-> triggers vasospasm)
3) lower rate of other CVRF

📍6/8 Angiography isn’t sensitive in diagnosis, bc bridge can’t be visualized.

1) Angiography: milking effect in systole
2) IVUS: half-moon sign w/ halo
3) iFR: functional evaluation
4) CTA: high resolution, descriptive
5) stress-echo: reversible septal buckling & apical sparing

📍7/8 Symptomatic myocardial bridging treatment
💊 first line: pharmacotherapy

🥇beta blockers (⬇️contractility & ⬆️ diastole)
🥈CCB (vasodilation & ⬆️ diastole)
🥉ivabradine (diastole⬆️)

🔪 Myotomy (60% late-recurrent CP) & 🔪 CABG (60% graft failure)
#CardioTwitter #CardioEd

8/8 sources:
@JACCJournals

jacc.org/doi/full/10.10…

doi.org/10.1253/circj.…

doi.org/10.1016/j.jcct…

doi.org/10.1016/j.ijca…

@AvrahamCooperMD @DjawidHashemi @blondemedSJW @fuzzymittens @escardio @Hannah_Billig_ @FH_Verbrugge @HolgerNef