Mitral Valve Disease

Anatomy

100

Ratio of posterior leaftlet to anterior leaflet perimeter

What is The annular perimeter of the posterior leaflet is longer than that subtending the anterior leaflet by a ratio of 2:1; ie, the posterior annulus circumscribes approximately two-thirds of the mitral annulus.

200

Collagenous structure of the mitral valve which is part of the central fibrous body.

What is the right fibrous trigone? the right fibrous trigone, which is part of the central fibrous body and is located at the intersection of the membranous septum, the tricuspid annulus, and the aortic annulus;

300

The posteromedial papillary muscle is supplied by this coronary artery.

What is the right coronary artery? The posteromedial papillary muscle usually is supplied by the right coronary artery (or a dominant left circumflex artery in 10% of patients); the anterolateral papillary muscle is supplied by blood flow from both the left anterior descending and circumflex coronary arteries.

400

This papillary muscle has one large prominent head.

What is the anterolateral papillary muscle?

500

This distance is relatively constant in normal hearts, but changes during acute ischemia due to papillary muscle dislocation.

What is the papillary-annular distance. The papillary-annular distances in the LV long axis remain relatively constant in normal hearts throughout the cardiac cycle.144 During acute ischemia, however, these distances change, which reflects repositioning or dislocation of the papillary muscle tips with respect to the mitral annulus. This can also contribute to apical tenting of the leaflets during systole.

**Squirrel

100

Timing of papillary muscle rupture after an MI

What is Papillary muscle rupture usually occurs 2 to 7 days after myocardial infarction; without urgent surgery, approximately 50 to 75% of such patients may die within 24 hours.

200

This percentage of patients with mitral valve prolapse progress to develop severe mitral regurgitation.

What is Only 5 to 10% of patients with mitral valve prolapse progress to develop severe mitral regurgitation, and they can surprisingly remain relatively asymptomatic until very late.179,180 Mechanisms accounting for severe mitral regurgitation in those with mitral valve prolapse include annular dilatation and rupture or elongation of the first-order chordae (58%), annular dilatation without chordal rupture (19%), and chordal rupture without annular dilatation (19%)

300

This is an associated finding in 50% of patients with severe mitral annular calcification?

What is aortic valve calcification?

400

These three factors (name 2) act in concert to maintain ejection performance after chordal-sparing mitral valve replacement.

What is smaller chamber size, reduced systolic afterload, and preservation of ventricular contractile function. Mitral valve replacement with complete chordal transection results in no postoperative change in LV end-diastolic volume, an increase in LVESV, an increase in ESS, and a decrease in ejection fraction.290 Patients who undergo chordal-sparing valve replacement, on the other hand, have a smaller LV end-diastolic volume and LVESV, decreased ESS, and unchanged ejection fraction. These findings suggest that smaller chamber size, reduced systolic afterload, and preservation of ventricular contractile function act in concert to maintain ejection performance after chordal-sparing mitral valve replacement. In contrast, increased LV chamber size, increased systolic afterload, and probable reduction in LV contractile function leading to reduced ejection performance occur in patients who undergo valve replacement with chordal transaction

500

What are two indications to operate on a patient with chronic mitral regurgitation?

What is patients with chronic mitral regurgitation should be referred for mitral valve surgery before LVESVI exceeds 40 to 50 mL/m2 or when LV end-systolic dimension reaches 4 cm, consistent with the 2006 American College of Cardiology/American Heart Association (ACC/AHA) practice guidelines

Mr. Rodgers - Won't you be my neighbor?

100

This coronary artery is most likely to be injured during a mitral valve operation.

What is the circumflex?

200

Conduction injuries are most likely to occur due to injury to this structure.

What is the membranous septum?

300

The membranous septum lives here (next to which trigone)

What is the right fibrous trigone?

400

This venous structure can be injured during a mitral valve surgery.

What is the coronary sinus?

500

Risk factors include extension decalcification, placement of an oversized valve, annular resection, and forceful retraction on the mitral valve apparatus. And how do you fix it

What is atrial-ventricular separation (discordance)?

Conjunction Junction What's your function

100

Mitral annular area changes by this much during the cardiac cycle

What is 20-40%? Annular size increases beginning in late systole and continues through isovolumic relaxation and into diastole; maximal annular area occurs in late diastole around the time of the P wave on the electrocardiogram.6,41,43,46,48 Importantly, half to two-thirds of the total decrease in annular area occurs during atrial contraction (or presystolic); this component of annular area change is smaller when the PR interval is short and is abolished completely when atrial fibrillation or ventricular pacing is present. Annular area decreases further (if LV end-diastolic volume is not abnormally elevated) to a minimum in early to midsystole.

200

Leaflet opening starts in this portion of the leaflet

What is the center of the leaflet. Leaflet opening does not start with the free margin but rather in the center of the leaflet; leaflet curvature flattens initially and then becomes reversed (making the leaflet convex toward the left ventricle) while the edges are still approximated.48,59,60 The leading edge then moves into the left ventricle (like a traveling wave), and the leaflet straightens. The leaflet edges in the middle of the valve appear to separate before those portions closer to the commissures, and posterior leaflet opening occurs approximately 8 to 40 ms later.60–63 Early leaflet opening (e wave) is very rapid; once reaching maximum opening, the edges exhibit a slow to-and-fro movement (like a flag flapping in a breeze) until another less forceful opening impulse occurs, associated with the a wave. During late diastole, the leaflets move gradually away from the LV wall.

300

The functional competence of the mitral valve relies on proper, coordinated interaction of the mitral annulus and leaflets, chordae tendineae, papillary muscles, left atrium, and left ventricle, what we refer to as this.

What is the valvular-ventricular complex?

500

Mitral leaflet stretch of 10% or more leads to this.

What is an action potential that initiates leaflet muscle contraction?

Gross Incompetence

100

These are 3 possible etiologies of mitral regurgitation.

What is Important causes of systolic mitral regurgitation include ischemic heart disease with ischemic mitral regurgitation (IMR), dilated cardiomyopathy [for which the general term functional mitral regurgitation (FMR) is used], myxomatous degeneration, rheumatic valve disease, mitral annular calcification, infective endocarditis, congenital anomalies, endocardial fibrosis, myocarditis and collagen-vascular disorders.83,86,87,136–138 IMR is considered a specific subset of FMR. Acute mitral regurgitation also may be the result of ventricular dysfunction from rapidly developing cardiomyopathy, such as Takotsubo cardiomyopathy, in which the mitral regurgitation is caused by left ventricular outflow tract obstruction and systolic anterior motion of the mitral valve from apical ballooning.

200

These general four types of structural changes of the mitral valve apparatus may produce regurgitation.

What is four types of structural changes of the mitral valve apparatus may produce regurgitation: Leaflet retraction from fibrosis and calcification, annular dilatation, chordal abnormalities (including rupture, elongation, or shortening), and LV dysfunction with or without papillary muscle involvement

300

This is the result of incomplete mitral leaflet coaptation in the setting of LV dysfunction and dilatation with or without annular dilatation.

What is functional mitral regurgitation?

400

Process characterized by large amounts of excessive leaflet tissue and marked annular dilatation are coupled with extensive hooding and billowing of both leaflets.

What is Barlow's syndrome? As strictly defined originally by John Barlow, Barlow's syndrome includes prolapse of the posterior leaflet and chest pain, and occasionally palpitations, syncope, and dyspnea; in younger patients, the initial clinical sign is a midsystolic nonejection click, which later evolves into a click followed by a late systolic murmur.179 This latter scenario is seen typically in young patients with Barlow's valves, in which large amounts of excessive leaflet tissue and marked annular dilatation are coupled with extensive hooding and billowing of both leaflets.

500

These are the three types of carpentier's functional classification of mitral regurgitation.

What is Carpentier classified mitral regurgitation into three main pathoanatomic types based on leaflet motion: normal leaflet motion (type I), leaflet prolapse or excessive motion (type II), and restricted leaflet motion (type III).140,141 Type III is further subdivided into types IIIa and IIIb based on leaflet restriction during diastole (type IIIa), as seen in rheumatic disease, or during systole (type IIIb), which is typically seen in IMR (Fig. 40-9)