B P8 C77 Tricuspid, Pulmonic, and Multivalvular Disease Flashcards
Tricuspid stenosis (TS) is almost always _____ in origin, although rheumatic valve disease more commonly affects left-sided valves.
Rheumatic
Other causes of obstruction to right atrial emptying are unusual and include
* Congenital tricuspid atresia
* Right atrial tumors, which may produce a clinical picture suggesting rapidly progressive TS
* Device leads, which more often are associated with tricuspid regurgitation (TR) but can become looped and fused to the tricuspid valve apparatus, and if multiple could cause obstruction.
* Carcinoid syndrome and use of ergot-related drugs more frequently produce TR, which if severe, contributes to a gradient across the tricuspid valve
* Dysfunction, including thrombosis, of a tricuspid mechanical or bioprosthetic valve can result in stenosis.
* Endomyocardial fibrosis, tricuspid valve vegetations, or extracardiac tumors cause obstruction to right ventricular (RV) inflow
* Localized compression of the right atrium by a pericardial effusion may also lead to RV inflow obstruction
A _____ between the right atrium and ventricle—the hemodynamic expression of TS—is augmented when the transvalvular blood flow increases during ____ and is reduced when the blood flow declines during _____.
Diastolic pressure gradient
Increases: inspiration or exercise
Reduced: Expiration
A relatively modest diastolic pressure gradient (i.e., a mean gradient of only _____ mmHg) usually is sufficient to elevate the mean right atrial pressure to levels that result in systemic venous congestion and, unless sodium intake has been restricted or diuretics have been given, is associated ultimately with jugular venous distention, ascites, and edema
5 mm Hg
In patients with TS with sinus rhythm, the right atrial a wave may be very ____ . Resting cardiac output usually is markedly reduced and fails to rise during exercise. This accounts for the normal or only slightly elevated left atrial, pulmonary arterial, and RV systolic pressures, despite the frequent presence of accompanying mitral valvular disease.
Tall a wave
A mean diastolic pressure gradient across the tricuspid valve as low as ___ mmHg and the typical echocardiographic appearance of leaflet restriction or doming is sufficient to establish the diagnosis of TS
2 mm Hg
Exercise, deep inspiration, and the rapid infusion of fluids or the administration of atropine may greatly enhance a borderline pressure gradient in a patient with TS
Some patients with TS complain of a fluttering discomfort in the neck, caused by _____ waves in the jugular venous pulse.
Giant a waves
_____ may greatly enhance a borderline pressure gradient in a patient with TS
Exercise
Deep inspiration
Rapid infusion of fluids
Atropine
Occasionally, the symptoms of MS (severe dyspnea, orthopnea, and paroxysmal nocturnal dyspnea) may be masked by severe TS because the latter prevents surges of blood into the pulmonary circulation behind the stenotic mitral valve. The absence of symptoms of _____ in a patient with obvious MS should suggest the possibility of TS.
Pulmonary congestion
In the presence of sinus rhythm (in patients with TS) , the ___ wave in the jugular venous pulse is tall, and a presystolic hepatic pulsation often is palpable.
The ___descent is slow and barely appreciable.
a wave: Tall
y descent: slow and barely appreciable
. A tricuspid opening snap (OS) may be audible but often is difficult to distinguish from a mitral OS. However, the tricuspid OS usually follows the mitral OS and is localized to the _____ border, whereas the mitral OS usually is most prominent at the apex and radiates more widely.
Lower left sternal border
The diastolic murmur of TS is also commonly heard best along the lower left parasternal border in the fourth intercostal space and usually is _____ than the murmur of MS.
Softer, higher-pitched, and shorter in duration
The diastolic murmur and OS of TS both are augmented by maneuvers that increase trans-tricuspid valve flow, including _____. They are reduced during _____.
Augmented by:
Inspiration
Mueller maneuver (forced inspiration against a closed glottis)
Right lateral decubitus position
Leg raising
Inhalation of amyl nitrite
Squatting
Isotonic exercise
Reduced by:
Expiration
Strain of the Valsalva maneuver
Return to control levels immediately (i.e., within two or three beats) after the Valsalva release
Severe TS is characterized by a valve area of ≤_____cm2 as assessed by the continuity equation. The pressure half-time is generally greater than _____ msec, and the right atrium and inferior vena cava are _____.
Valve area: ≤ 1 cm2
PHT > 190 ms
Dilated RA and IVC
The mean pressure gradient across the tricuspid valve varies with heart rate, but a mean gradient ≥ ≥ ____ mm Hg is consistent with significant TS.
≥ 5 mm Hg
The key radiologic finding in TS is _____(i.e., prominence of the right heart border), which extends into a dilated superior vena cava and azygos vein, but without conspicuous dilation of the pulmonary artery.
Marked cardiomegaly with conspicuous enlargement of the right atrium
Imaging and ECG findings in TS
ECG: tall right atrial P waves, no RVH
CXR: Dilated RA w/o enlarged PA
2D Echo: diastolic doming of TV leaflets, thickening of valve, diastolic pressure gradient across tricuspid valve, right atrial enlargement
Although the fundamental approach to the management of severe TS is _____ treatment, _____ therapy may diminish those symptoms secondary to the accumulation of excess salt and water.
Surgical
Intensive sodium restriction and diuretic therapy
A preparatory period of diuresis may diminish hepatic congestion, thereby improving hepatic function sufficiently to diminish the risks of subsequent operation.
Surgical treatment of TS should be carried out at the time of mitral valve repair or replacement in patients with TS in whom the mean diastolic pressure gradient exceeds _____ mm Hg and the tricuspid orifice is less than approximately 2.0 cm2
Mean diastolic PG > 5 mm Hg
Orifice < 2.0 cm2
A large ______ is preferred to a mechanical prosthesis in the tricuspid position because of the high risk of thrombosis of the latter and the longer durability of bioprostheses in the tricuspid than in the mitral or aortic positions.
Bioprosthesis
Because TS almost always is accompanied by some TR, simple finger fracture valvotomy may not result in significant hemodynamic improvement but may merely substitute severe TR for TS.
However, open valvotomy or commissurotomy in which the stenotic tricuspid valve is converted into a functionally bicuspid valve may result in improvement, but annuloplasty may also be necessary if annular dilatation is present.
The commissures between the anterior and septal leaflets and between the posterior and septal leaflets are opened. It is not advisable to open the commissure between the anterior and posterior leaflets for fear of producing severe TR
The most common cause of TR is not intrinsic involvement of the _____ but rather dilation of the right ventricle and of the tricuspid annulus causing secondary (functional) TR
Valve itself (i.e., primary TR)
Right heart dilatation may result from volume overload as seen with left-to-right shunts in atrial septal defects or anomalous pulmonary venous connections.Dilatation may be a com- plication of RV failure of any cause
In general, a RV systolic pressure greater than _____ mm Hg will cause functional TR.
55 mm Hg
In the absence of pulmonary hypertension or RV failure, TR generally is well tolerated.
When pulmonary hypertension and TR coexist, cardiac output declines and the manifestations of right-sided heart failure become intensified.
Thus, the symptoms of TR result from a ____.
Reduced cardiac output and from ascites, painful congestive hepatomegaly, and massive edema
In patients with severe TR, evidence of _____ are often present on inspection.
Weight loss and cachexia
Cyanosis
Jaundice
PE findings in TR
- Jugular venous distention, the normal x and x’ descents disappear, and a prominent systolic wave – a c-v wave (or s wave)
- y descent, is sharp and becomes the most prominent feature of the venous pulse except with coexisting TS, in which case it is slowed.
- Venous systolic thrill and murmur in the neck may be present in patients with severe TR.
- RV impulse is hyperdynamic and thrusting in quality.
- Initially, systolic pulsations of an enlarged tender liver are frequent. However, in patients with chronic TR and congestive cirrhosis, the liver may become firm and nontender.
- Ascites and edema are frequent.
