Pocket Medicine: The Massachusetts General Hospital Handbook of Internal Medicine (13 page)

• Congestive hepatomegaly, ± ascites and jaundice, peripheral edema
Diagnostic studies

• CXR: normal ventricular chamber size, enlarged atria, ± pulmonary congestion • ECG: low voltage, pseudoinfarction pattern (Qw), ± arrhythmias • Echo: symmetric wall thickening, biatrial enlarge., ± mural thrombi, ± cavity oblit. w/ diast dysfxn: ↑ early diast (E) and ↓ late atrial (A) filling, ↑ E/A ratio, ↓ decel. time • Cardiac MRI/PET: may reveal inflammation or evidence of infiltration (but nonspecific) • Cardiac catheterization

Atria:
M’s
or
W’s
(prominent
x
and
y
descents)

Ventricles:
dip & plateau
(rapid ↓ pressure at onset of diastole, rapid ↑ to early plateau)

Concordance
of LV and RV pressure peaks during respiratory cycle (vs. discordance in constrictive pericarditis;
Circ
1996;93:2007)

• Endomyocardial biopsy if suspect infiltrative process • Restrictive cardiomyopathy vs. constrictive pericarditis: see “Pericardial Disease”

Treatment (in addition to Rx’ing underlying disease)

• Gentle diuresis. May not tolerate CCB or other vasodilators.

• Control HR (but can ↓ CO); maintain SR (helps filling). Digoxin ↑ arrhythmias in amyloid.

• Anticoagulation (particularly with AF or low CO) • Transplantation for refractory cases

VALVULAR HEART DISEASE

AORTIC STENOSIS (AS)

Etiology

•
Calcific
: predominant cause in Pts >70 y; risk factors include HTN, ↑ chol., ESRD

•
Congenital
(ie, bicuspid AoV w/ premature calcification): cause in 50% of Pts <70 y •
Rheumatic heart disease
(AS usually accompanied by AI and MV disease) • AS mimickers: subvalvular (HCMP, subAo membrane) or supravalvular stenosis
Clinical manifestations (usually indicates AVA <1 cm
²
or concomitant CAD)

•
Angina
: ↑ O
₂
demand (hypertrophy) + ↓ O
₂
supply (↓ cor perfusion pressure) ± CAD

•
Syncope
(
exertional
): peripheral vasodil. w/ fixed CO → ↓ MAP → ↓ cerebral perfusion •
Heart failure
: outflow obstruct + diastolic dysfxn → pulm. edema; esp. if ↑ HR/AF (↓ LV fill.) • Acquired vWF disease (~20% of sev. AS): destruction of vWF; GI angiodysplasia • Natural hx: usually slowly progressive (AVA ↓ ~0.1 cm
²
/y, but varies;
Circ
1997;95:2262), until sx develop; mean survival based on sx: angina = 5 y; syncope = 3 y; CHF = 2 y
Physical exam

•
Midsystolic crescendo-decrescendo
murmur at
RUSB
, harsh, high-pitched, radiates to carotids, apex (holo-systolic = Gallavardin effect), ↑ w/ passive leg raise, ↓ w/ standing & Valsalva. In contrast, dynamic outflow obstruction (HCMP) ↓ w/ leg raise, ↑ w/ standing, Valsalva.

• Ejection click after S1 sometimes heard with
bicuspid
AoV

• Signs of severity:
late-peaking
murmur, paradoxically split S
₂
or inaudible A
₂
, small and delayed carotid pulse (“
pulsus parvus et tardus
”), LV heave,
S
₄
(occasionally palpable)

Diagnostic studies

• ECG: may see LVH, LAE, LBBB, AF (in late disease) • CXR: cardiomegaly, AoV calcification, poststenotic dilation of ascending Ao, pulmonary congestion •
Echo
: valve morphology, estim pressure gradient & calculate AVA, EF

•
Cardiac cath
: usually to
r/o CAD
(in ~½ of calcific AS); for hemodyn. if disparity between exam & echo: ✓ pressure gradient (∇) across AoV, calc AVA (underestim. if mod/sev AI) •
Dobutamine challenge
during echo or cath if low EF and ∇ <30 to differentiate:
afterload mismatch:
20% ↑ SV & ∇, no Δ AVA (implies contractile reserve & ↑ EF post-AVR)

pseudostenosis:
20% ↑ SV, no Δ in ∇, ↑ AVA (implies low AVA
artifact
of LV dysfxn)

limited contractile reserve:
no Δ SV, ∇ or AVA (implies EF prob. will not improve w/ AVR)

Treatment (
Circ
2008;118:e523;
Lancet
2009;373:956;
EHJ
2012;33:2451)

• Management decisions are based on
symptoms
: once they develop AVR is needed.

If asx, HTN can be cautiously Rx’d; statins have not been proven to ↓ progression.

•
AVR
: indicated in
sx AS
(almost invariably severe; if not, look for another cause of sx) &
asx severe AS
+
EF
< 
50%.
May consider if
asx
but
either sx or
↓
BP w/ exercise
(can
carefully
exercise asx AS to uncover sx, do
not
exercise sx AS) or
extremely severe
(AVA <0.6 cm
²
, mean ∇ >60 mmHg, aortic jet >5 m/s). Reasonable if asx mod-severe AS
and
undergoing CV surgery.

• Medical (if not AVR candidate or to temporize): careful diuresis prn, control HTN, maintain SR; digoxin if ↓ EF & HF or if AF;
avoid
venodilators (nitrates) &
inotropes (bB/CCB) if severe; avoid vigorous physical exertion once AS mod–severe;

? nitroprusside if p/w CHF w/ sev. AS, EF <35%, CI <2.2, & nl BP (
NEJM
2003;348:1756)

• IABP: stabilization, bridge to surgery • Balloon AoV valvotomy (BAV): 50% ↑ AVA & ↓ peak ∇,
but
50% restenosis by 6–12 mo &

↑ risk of peri-PAV stroke/AI (
NEJM
1988;319:125), ∴ bridge to AVR or palliation

•
Transcatheter AoV replacement (TAVR)
:
sx, hemodyn, & mortality to surgical AVR, but ↑ (mostly early) risk of vasc complic and stroke/ TIA; paravalvular leaks in ~7% (
NEJM
2012;366:1686); in nonoperative Pts, 44% ↓ mortality vs. standard Rx (
NEJM
2012;366:1696)

AORTIC INSUFFICIENCY (AI)

Etiology (
Circ
2006;114:422)

•
Valve disease
(43%)
rheumatic heart disease
(usually mixed AS/AI and concomitant MV disease)
bicuspid AoV
: natural hx:
¹
⁄
₃
→ normal,
¹
⁄
₃
→ AS,
¹
⁄
₆
→ AI,
¹
⁄
₆
→ endocarditis → AI
infective endocarditis

valvulitis: RA, SLE; anorectics (fen/phen) & other serotoninergics (
NEJM
2007;356:29,39), XRT

•
Root disease
(57%)

HTN

aortic aneurysm or dissection, annuloaortic ectasia, Marfan syndrome

aortic inflammation: giant cell, Takayasu’s, ankylosing spond., reactive arthritis, syphilis

Clinical manifestations

• Acute: sudden ↓ forward SV and ↑ LVEDP (noncompliant ventricle) → pulmonary edema ± hypotension and cardiogenic shock • Chronic: clinically silent while LV dilates (to ↑ compliance to keep LVEDP low) more than it hypertrophies → chronic volume overload → LV decompensation → CHF

• Natural hx:
variable
progression (unlike AS, can be fast or slow); once decompensation begins, prognosis poor w/o AVR (mortality ~10%/y)
Physical exam