Ingxenyana ye-ejection iyinkinga yezilinganiso ezivame ukusetshenziswa ukuhlola ukuthi inhliziyo ikwazi kanjani ukupompa igazi. Ngokucacile, ingxenyana ye-ejection iyinani legazi eliphambuka kusuka engxenyeni engakwesokunxele (ekamelweni eliyinhloko lokushaya amanzi) ngenhliziyo ngayinye.
Ngokuvamile, i-ventricle engakwesokunxele ibamba umthamo ngamunye ngamaphesenti angu-55 noma ngaphezulu wegazi layo, ngakho-ke ingxenyana "evamile" ye-ejection ingu-55% (0.55) noma ngaphezulu.
Ingxenyana ye-ejection ye-40 - 50% ithathwa ngokuthi "ngaphansi kwesimiso esivamile." Iziguli ezinokuhluleka kwenhliziyo kaningi ziba nezinhlamvu ezingaphansi kuka-40%.
I-terminology ye "Ejection Fraction"
Kubalulekile ukuqaphela ukuthi uma odokotela bethi amagama athi "ingxenyana ye-ejection" abhekisela engxenyeni ye-ejection ye-ventricle engakwesokunxele. Ngokufanelekile lokhu kuzobizwa ngokuthi "ingxenyana ye-ventricular ejection" noma "LVEF" futhi ngezinye izikhathi ungase ubone noma uzwe leli gama.
I-ventricle efanele nayo ineqhezu layo le-ejection ("ingxenyana ye-ventricular ejection," noma i-RVEF). Kodwa-ke, i-RVEF ayisho kaningi noma ingakhulunywa ngabadokotela (ngenxa yokuthi kunzima kakhulu ukulinganisa kune-LVEF, futhi ngenxa yokuthi ukwazi i-RVEF eqondile ngokuvamile akusizi ngokukhethekile.)
Uma udokotela wakho ethi "i-fraction ejection," ubhekisela ku-LVEF.
Kungani Izifo Zenhliziyo Zinye Ngezinye izikhathi Zenza Ukuhlukaniswa Kwe-Ejection Fraction?
Lapho imisipha yenhliziyo iba buthakathaka, imicu ye-muscle ayikwazi ukuthenga ngokugcwele.
Okusho ukuthi ukunciphisa imisipha ye-muscle eyenzeka nge-muscle contraction iyancipha. Lokhu kusho ukuthi, ngaphandle uma kukhona isinxephezelo somsebenzi omfutho we-muscle, inani legazi eliphambanwe ngenhliziyo ngayinye (" umthamo wokushaya ") lizokwehlisa.
Ukuze uhlawulele lokhu okungahambi kahle, inhliziyo iyancipha, ivumela ivolumu yesifo esivamile (noma esiseduze) evamile ukuba igcinwe naphezu kokuncipha kwe-muscle fiber.
Lokhu kuhlunga kusho ukuthi inani legazi elikhishwa ngesikhathi senhliziyo ngayinye liyancipha (okungukuthi, i-fraction ejection iwa) - kodwa ivolumu yokushaya isisindo ihlala ezingeni elingajwayelekile.
Elinye igama lokunciphisa inhliziyo enesixazululo esikhombisa isifo senhliziyo isisusa "ukulungiswa."
I-Ejection Fraction ilinganiselwa kanjani?
Ingxenyana ye-ejection ivame ukulinganiswa nge- echocardiogram , kodwa ingabuyekezwa nge- scan ye-MUGA noma ngesikhathi se- cardiac catheterization . Ukuskena kwe-MUGA ngokuvamile kuyindlela enembile kakhulu yokukhiqiza ingxenyana ye-ejection, futhi ngokuvamile isetshenziswa ezimweni lapho kudingeka khona izilinganiso eziphindaphindiwe, eziqondile; ngokwesibonelo, uma i-chemotherapy isetshenziselwa ukuthi ibe yingozi kunezinhlanzi zenhliziyo - ngokuvamile, i- doxorubicin (i-Adriamycin) .
Odokotela basebenzisa kanjani isilinganiso se-Ejection Fraction?
Ingxenyana ye-ejection iwusizo njengesilinganiso samandla jikelele enhliziyo. I-lower engxenyeni ye-ejection, ebuthakathaka isisindo senhliziyo (njengoba ukuhlanza kwenhliziyo kuyadingeka ukugcina ivolumu yesifo senhliziyo). Uma ingxenyana ye-ejection iwa, lokho ngokuvamile kusho ukuthi imisipha yenhliziyo iya buthakathaka. Ingxenyana ekhulayo ye-ejection ngokuvamile isho ukuthi amandla e-muscle enhliziyo ayathuthuka.
Odokotela basebenzisa i-ejection fraction measurement for diagnosis of cardiomyopathy , ukuhlola ukusebenza kwetherapi yezokwelapha ekuqiniseni noma ekuthuthukiseni ukuhluleka kwenhliziyo, nokunquma ngezindlela ezingcono zokwelashwa zokuhluleka kwenhliziyo.
Isibonelo, ingxenyana ye-ejection engaphansi kwezingu-35% yandisa kakhulu izigulane zesiguli zokuboshwa komzimba , futhi ngokujwayelekile kufanele iqhube ingxoxo yomuntu ongenamakhemikhali .
Imithombo:
Lang RM, Bierig M, Devereux RB, et al. Izincomo ze-quantification ekamelweni: umbiko ovela kwiKomidi Lezinkombandlela Nezilinganiso ze-American Society of Echocardiography kanye neQembu le-Quantification Writing, elenziwe ngokubambisana ne-European Association of Echocardiography, igatsha le-European Society of Cardiology. J Am Soc Echocardiogr 2005; 18: 1440.