Vaše srce kuca više od 100,000 puta dnevno. U samo minuti ispumpa preko pet litara krvi kroz cijelo tijelo. Ali za razliku od kože i kostiju, srce ima ograničenu sposobnost samooporavka. Stoga ako je ovaj organ veoma oštećen, postoji često samo jedno rješenje: zamijeniti ga. Danas, skoro 3,500 transplantacija srca se urade svake godine u kompleksnoj i zamršenoj proceduri bez prostora za pogrešku.
Your heart beats more than 100,000 times a day. In just a minute, it pumps over five liters of blood throughout your body. But unlike skin and bones, the heart has a limited ability to repair itself. So if this organ is severely damaged, there’s often only one medical solution: replacing it. Today, nearly 3,500 heart transplants are performed each year in a complex and intricate procedure with no room for error.
Proces se započinje testiranjem potencijalnih primalaca kako bi bilo sigurno da su dovoljno zdravi za ovu zahtjevnu operaciju. Doktori su naročito zabrinuti sa detekcijom imunokompromitirajuće bolesti ili bilo kojih drugih stanja koja bi mogla ugroziti šansu pacijenta da preživi.
The process begins by testing potential recipients to ensure they’re healthy enough for this demanding operation. Doctors are especially concerned with identifying immunocompromising illnesses or any other conditions that could compromise a patient's chance of survival.
Sljedeći korak je povezati odgovarajućeg primaoca sa donorom srca. Donori su često komatozni pacijenti bez šanse da budu reanimirani ili žrtve fatalnog događaja čija su srca idalje zdrava. U oba slučaja, ovi pacijenti treba da budu registrovani kao donori organa ili da njihove porodice dadnu pristanak. Čak i kada je srce dostupno, hirurzi ne mogu spojiti bilo kojeg donora sa bilo kojim primaocem. Imuni sistem primaoca će vidjeti transplantirano srce kao strani organizam koji mora biti napadnut. Doktori treba da usklade primaoce sa donorima koji dijele krvnu grupu i imaju slične antigene.
The next step is to match an eligible recipient with a heart donor. Donors are often comatose patients with no chance of being resuscitated or victims of a fatal event whose hearts are still healthy. In both cases, these patients need to be registered as an organ donor or have their families give consent. And even when a heart is available, surgeons can’t just pair any donor with any recipient. The recipient’s immune system will view a transplanted heart as a foreign organism that must be attacked. So doctors need to match recipients with donors that share their blood type and have similar antigens.
Ako je kompaktibilnost moguća, operacija može početi. Kada se potvrdi da je srce donora zdravo, organ se uranja u led i ubrizgava rastvorom da inducira zastoj srca. Ovim tretmanima se zaustavlja srce od pumpanja i osigurava da se ono može ukloniti čisto. Hirurzi potom stavljaju organ u mješavinu hladne fiziološke otopine i otopinu konzervansa.
If a match can be made, the surgery can begin. Once the donor's heart is confirmed to be healthy, the organ is immersed in an ice slush and injected with a solution to induce cardiac arrest. These treatments stop the heart from pumping to ensure it can be removed cleanly. Surgeons then place the organ in a mix of cold saline and preservation solution.
Tada počinje vrijeme otkucavati. Odspojene od snabdjevanja krvlju, srčane ćelije počinju preuzimati štetu zbog nedostatka oksigena. Organ će samo ostati održiv izvan tijela nekoliko sati, stoga treba doći do svog primaoca što je prije moguće.
This is when the clock starts. Disconnected from its blood supply, the heart’s cells start taking on damage from lack of oxygen. The organ will only remain viable outside the body for a few hours, so it needs to reach its recipient as fast as possible.
Onog momenta kada srce pristigne, primalac je stavljen pod opću anesteziju. Hrirurg pravi rez duž prsa, sjekući prsnu kost da bi se razdvojio prsni koš i izložilo srce. Kako bi se održao protok krvi dok se uklanja oštećeni organ, hirurzi koriste kardiopulmonarni bajpas. On preuzima posao srca, proizvodeći dovoljno energije da gura krv kroz krvni tok pacijenta.
Once the heart arrives, the recipient is put under general anesthesia. The surgeon makes an incision down the length of the chest, cutting through the breastbone to separate the rib cage and expose the heart. To keep blood flowing while they remove the damaged organ, surgeons use a cardiopulmonary bypass machine. This takes over the heart's job, generating enough force to push blood through the patient's circulatory system.
Nakon uklanjanja starog srca, hirurg započinje prišivati donorsko srce na mjesto. Ovo je nevjerovatno precizan proces, gdje svaka krvna žila i arterija mora biti pažljivo pripojena da ne bude curenja. Procedura može potrajati i nekoliko sati, čak i duže ako postoji ožiljkasto tkivo od prethodnih operacija. Kada je gotovo, bajpas se gasi i krvi se omogućava protok do aorte. Doktori pažljivo prate novo srce kako bi bili sigurni da može samo kucati prije nego zašiju primaoca.
After the old heart is removed, the surgeon begins sewing the donor heart into place. This is an incredibly precise process, where each blood vessel and artery must be carefully attached to avoid leaks. The procedure can last several hours, potentially longer if there’s scar tissue from previous surgeries. Once it’s finished, the bypass machine is turned off and blood is allowed to flow into the aorta. Doctors carefully monitor the new heart to ensure it’s beating on its own before sewing the recipient back up.
Čak i kada je procedura gotova, postoji još posla koji se mora uraditi. Hirurzi nemaju sposobnost da direktno povežu srce sa nervnim sistemom primaoca, i mogu biti potrebne godine za tijelo da u potpunosti inerviše novi organ. Tokom ovog perioda, trasnplantirani organ ima više otkucaja srca u mirovanju i rizik od udara, čineći vježbu teškom i opasnom. I pošto je nevjerovatno rijetko naći savršen spoj između donora i primaoca, imuni sistem će također odgovoriti na novo srce. Imunuosupresivi mogu pomoći pri upravljanju rizika od odbacivanja, ali također ostavljaju pacijente sklonima razvoju opasnih infekcija. Potrebno je stalno nadziranje i testiranje da bi se uravnotežila ova dva problema
Even after the procedure is complete, there's still work to be done. Surgeons are unable to directly connect the heart to the recipient’s nervous system, and it can take years for the body to fully innervate the new organ. During this period, the transplanted organ has a higher resting heart rate and risk of stroke, making exercise difficult and dangerous. And since it’s incredibly rare to find a perfect match between donor and recipient, the immune system will also have some response to the new heart. Immunosuppressive drugs can help manage the risk of rejection, but they also leave patients open to contracting dangerous infections. It requires constant monitoring and testing to balance these two concerns.
Uprkos ovim izazovima, oko 70% primalaca transplantiranog srca požive još najmanje pet godina nakon operacije, i preko 20% narednih 20 godina. Kada je procedura uspješna, zaista je spasonosna. Nažalost, ljudi u zemljama u razvoju često nemaju mogućnost pristupa ovoj operaciji, i mnoga vitalna srca ne mogu biti donirana zbog pravnih i regulatornih problema. Hiljade ljudi ostaju na listi čekanja, a mnogi nikada ne mogu pronaći odgovarajućeg donora.
Despite these challenges, about 70% of heart transplant recipients survive for at least five years after the operation, and just over 20% live another 20 years. So when this procedure is successful, it's truly lifesaving. Unfortunately, people in developing countries are often unable to access this surgery, and many viable hearts can’t be donated due to legal and regulatory issues. Thousands of people remain on waiting lists, and many are never able to find a suitable donor.