normal myocard; myocardial hypertrophy ICD-10: I51.7
Mann, 48 J., Unfalltod
Frau, 76 J., arterielle Hypertonie. Verstirbt an einer Massenblutung
des Gehirns
Autopsiepräparate
Im Vergleich zum normalen Myokard weist
das hypertrophe Myokard folgende Veränderungen auf:
- Die Myokardiozyten sind im Querschnitt breiter (Zahl der kontraktilen
intrazellulären Filamente erhöht)
- Oft ist der Kern deutlich vergrössert("Elefantenkerne", vergrösserter Kern). Vergleichsmassstab: Fibrozytenkerne
oder Erythrozyten
- Die Zahl der Kapillaren ist erhöht
Pathogenese:
Druckbelastung infolge erhöhter Resistenz im arteriellen Kreislauf,
z.B. bei Hypertonie oder/bzw. bei Aortenstenose
Makroskopie:
Myokard der Kammer mit erhöhter Druckbelastung verdickt, Herzgewicht
über die Norm erhöht
48-year-old male died in an accident.
76-year-old female suffered from arterial hypertension and died because of massive cerebral hemorrhage (specimens from autopsy).
-Two sections of the left ventricular wall are shown, the one to the right exhibits slight, the one to left
severe hypertrophy of the myocardium.
- In cardiac hypertrophy (hypertrophe Myokard) the following histological characteristics can be observed: (1) Increased cross-sectional areas of myocytes due to an increased
number of sarcomeres; (2) Nuclei are enlarged (vergrösserter Kern, as a scale compare with erythrocytes or nuclei of fibroblasts; (3) The capillary density is decreased compared
to normal; (4) A marked fibrosis may be present. (5) The muscle fibers display branching, so called muscle fiber disarray. This feature is reminiscent of
hypertrophic cardiomyopathy.
- In the section to the right the slight enlargement of nuclei can be appreciated. However, the other features described above are not present. In contrast,
the section to the left displays all features stated.
Pathogenesis: Increased pressure load due to an increased resistance (arterial hypertension, aortic valve stenosis).
Macroscopy: Increased wall thickness of the left ventricle. The thickened muscle may reduce the cavity diameter. The weight of the heart is increased above normal levels. Pressure-overload leads to so called concentric hypertrophy.