Dogs Don't Get Heart Attacks, But They Do Get This

Hemoabdomen cases seem to come out of nowhere

April 20, 2015 (published)

There are all sorts of pluses and minuses to the world of veterinary medicine when compared to human medicine, but in one area veterinarians come up clear winners: In all but the most vanishingly rare situations, dogs don’t get heart attacks.

Dogs almost never develop the same sort of hardening of the arteries, known as atherosclerosis, that makes middle-aged men and women clutch their chests, drop the 3-wood and shuffle off this mortal coil. Human medicine has all the shiny toys, insurance money and human-life-is-so-important stuff going for it that it makes veterinarians green with envy, but I thank my lucky stars every day that I don’t have to deal with heart attacks.

The canine equivalent, at least in my opinion, is probably a phenomenon known as ‘spontaneous hemoabdomen' even though it is not related to coronary artery disease. Your average veterinary ER probably sees two or three of these types of cases a week, and as the pet population ages they are bound to become even more common.

The thing about hemoabdomen cases that makes them so frightening for pet owners is that they seem to come out of nowhere, and they hit like a random, unforeseen lightning strike on an otherwise sunny day - like a human heart attack. One moment their dog may be happily cavorting in the yard, and the next they’re lying on a gurney in a veterinary ER fighting for their lives.

In most cases, a tumor on the spleen, which may have been growing for weeks in the abdomen without being detected, ruptures and starts to hemorrhage internally. This condition is called hemangiosarcoma. Dogs can bleed to death within a few hours if the bleeding continues unchecked. They can be quite literally felled in their tracks.

The bleeding is internal, and there is no evidence of bleeding that can be seen externally by the pet owner. All they know is that their dog was fine one minute, then collapsed and couldn’t get up the next. No blood in the stool, none in the urine, none anywhere; just a big pool of blood building up inside the abdominal cavity. Blood that should be circulating and bringing oxygen to tissues is suddenly settling in the abdomen. Shock and low blood pressure set in almost immediately.

The signs are typically a sudden onset of weakness and inability to get up. These can happen in any breed of dog, but the majority are in dogs that share a genome with German Shepherds. Golden Retrievers, sadly, probably take the number two spot. Any dog over eight years old that’s related to a German shepherd or Golden is potentially at risk for a spontaneous hemoabdomen, and this disease should be considered in any dog of this type who has a sudden episode of unexplained weakness. Check their gums, as they are often as white as a sheet during this event.

In about three quarters of the cases, the ruptured mass on the spleen is due to an aggressive malignancy called a hemangiosarcoma, a really nasty cancer that grows out of blood-forming organs (the spleen is a tongue-shaped, flat organ that sits on the left side of the abdomen, all snuggled up to the kidneys and other giblets). Hemangiosarcomas love to grow rapidly, spread to other parts of the body and, worse, they usually eat powerful chemotherapeutic drugs for lunch. It is just a miserable type of cancer to have, and most patients with them are not around for long, even with a full-court press of medical intervention. I hate diagnosing hemangiosarcoma because it usually means I have just pronounced a death sentence for a patient.

For that lucky one out of four that doesn’t have a hemangiosarcoma, they likely have a benign and slow-growing tumor called a hemangioma that just decided to break open and start bleeding (we keep the names similar to confuse the tourists). These, fortunately, can be completely cured through surgery. You still have to deal with all that life-threatening hemorrhage and accompanying scariness, but at least you get good news when the biopsy comes back.

The survival rate for dogs with hemangiosarcoma after emergency surgery to stop the bleeding is, on average, about three months. That time span can be doubled with the help of powerful chemotherapy, which is an option that all owners should be offered. We tend to not be as aggressive with chemo for our pets as they are with people, so that can mean fewer side effects. For some folks, six months of good quality life is a blessing, while for many that is nowhere near enough to justify the medical high-wire act that must happen to even hope for a little survival. The word ‘cure’ is almost never uttered in the same sentence as the word ‘hemangiosarcoma.’

Many owners decide to not pursue surgery when we make the diagnosis of hemoabdomen, and I can’t blame them. They are usually looking at a 75% chance that their dog has a disease that will very likely kill them inside of 90 days. The alternative is a fast and painless euthanasia, or, in some special cases, a death at home. Despite all the drama of this disease, it is usually totally painless and I will honor requests to take pets home to die if the owners are educated about what may happen. For those that elect to pursue treatment (I would say about one-third to one-half of owners opt to treat), the goal is to take them to surgery as soon as they are stabilized. This means blood transfusions and other methods to try and make them the best anesthesia candidate we can, quickly.

All of this comes at owners with dizzying speed. I am often in the unenviable position of trying to get them to make a timely decision on a very expensive, delicate matter with little information and no guarantees. Unfortunately, lengthy Q&A sessions in the middle of this type of crisis only makes the prognosis grow more dim for the patient as their lifeblood seeps into their abdominal cavity. I have had patients go from the front door to the surgery suite in under an hour, and sometimes with only the briefest of introductions of myself to the pet owner.

However, I recognize the need for people to feel that they have made the best and most informed decision that they can in this scenario. I try to answer as many questions as time permits for the patient, and steer them to make a decision if we start covering the same ground repeatedly. I want to note one important point right here. This is an excruciatingly difficult point in the lives of pet owners, and it becomes a critical juncture for me to talk to the owners, hear their concerns, and help them make the best decision we all can, given the imperfect information we have on hand. Unfortunately, in this case the patients simply don’t have time for anything but a rapid decision.

The cost for surgery and ICU aftercare can easily run into the thousands (many will hit the $5,000 mark before discharge), and many will have post-op complications that can escalate that amount.

I had one case several years back where post-op complications kept the dog in the hospital for a week, at a cost of over $10,000. The biopsy came back shortly after discharge and was what we all feared worst: hemangiosarcoma. The dog, owned by a very nice and caring physician, lived for another month before the cancer grew back and caused more bleeding. For most of us, $10,000 for another month of life would never fit the budget (or, for some people, their concept of what is right), but for this man, he assured me it was the best month he ever had with his dog. They hiked, they fished, they lounged on the couch eating Doritos and drinking Yoo-Hoo. They did everything but go 2.7 seconds on a bull named Fu Manchu. They lived like the dog was dying, and got everything out of it they could. He was happy with his initial decision and told me, as I put his dog to sleep, that he would have made it again.

For a bad outcome, that’s a pretty good way to look at it.


Mary Anne Kochut
November 17, 2020

This happened to my beloved Wolfie on November 3rd. I had no idea what was going on and rushed him to the hospital. Wolfie was a certified therapy dog and brought job and comfort to people in the hospital and cancer center. I'm heartbroken beyond words. I came across this article searching for answers to see if there was anything I could have done. It's a little comforting to know that I made the 'right' choice, no matter how painful it was for me.

November 17, 2020

My family just lost our 6 year old border collie to this. It happened so suddenly.

November 8, 2020

Our Romeo is an 11 y/o standard poodle, who was diagnosed with hemangiosarcoma a week ago.  Romeo also has addison and heart murmur; his doctor did not recommend a splenectomy. After the vet visit, we came home with some pain medication and was advised to call whenever we are ready to put Romeo to sleep. Today is the 7th day Romeo has been taken I'm-Yunity + Yunnan Baiyao. He is still very weak but starts showing signs of progress. Most importantly, his breath doesn't smell as bad as it used to the past few months. We're keeping our fingers crossed.

November 7, 2020

Lost out beautiful girl Ruby just yesterday. She was a lab and celebrated her 14th birthday two weeks ago. I have never heard of this condition in a dog and I had no idea that it is so common. Pleased to find this site as now I know we made the right decision for her. RIP my lovely Rubes

October 22, 2020

Oct 4th I lost my Bella dog. We adopted her and sobwe think she was 12 or 13 now we fist thought she was 10 or 11years and had her for 9years. She always had grade 2 mast cells removed had a lymphoma and melonima removed. The morning of October 2nd she peed two big piles in my bed and didn't want to get up so I moved her off and then downed a whole water bowl. At first I thought she maybe had a bladder infection or something. I went out for an hour came back and she was not moving laying in clear liquid pile. I coaxed her to at least walk out the front door, she's 70lbs) and I picked her up in the car. Her body felt cold, pale gums and her mouth felt like sticking your hands in a bunch of ice cubes. The vet tech picked her up put of the car bc Bella could not move. I told them what was going on so 3mins later the vet comes in and right away draws blood out of her abdomen and said with her history of tumors she more then likely has one in her abdomen. He performed the surgery to remove her spleen due to that being the ruptured tumor. All her blood work and images looked great. He calls us Saturday night tells us he's confident she will recover shes eating and walking using the bathroom. Sunday oct4th 830am he tells us she didn't make it which he then strongly suspected it being cancer and the rupture resulted in overwhelming her bodys ability to fight it. She was on good pain meds and the vet stayed with her all weekend so she wasn't alone. We got the biopsy back confirming hemogroscorma. Two days before this her body felt a little cool and I thought it was from the windows bring open or cool inside and I will never forget by the time we got to the vets office her brown eyes turned so so dark almost black. Cancer is no joke no matter how many tunors you remove and survive. She was a special soul and a beating rottie shepherd mix. I hope everyone here can find the good and love they remember giving their furbabies.

October 20, 2020

This happened to my sweet yellow lab a year ago today. That morning started like every morning-she went outside, chased deer, came inside. I put her breakfast out and when she didn't come to get it, I found her lying on her side in the next room, already in shock, barely breathing, eyes wide, immobile. I knew there wasn't time to take her anywhere so I just knelt beside her and stroked her head and told her it was ok to go. She died in less than five minutes. Later when I moved her, it was obvious what had happened--that she had bled out internally. She was nine. In retrospect, the only signs in the weeks beforehand were slightly pale gums and some odd dry coughing,  The good news is she didn't suffer and she had a full life right up to the very end. I share this because before it happened I didn't know anything about Hemangiosarcoma and it helped me to talk to other people--vets and owners--who had experienced this devastating disease.

October 18, 2020

Less than 24 hours ago we had our beautiful 10.5 year old lab euthanized. It all went down in less than a couple hours from beginning to end. This dog is tough as nails and was doing zoomies in the backyard and finding pheasants just the day before. I kenneled him for about 45 minutes bc he was barking and being rambunctious out the window as usual. Came back to let him out and offered him a treat. He wouldn’t take it. This dog has never turned down food ever. He laid down in front of his treat and closed his eyes. It broke my heart right there I felt he was gone... his breathing was shallow and he was very unresponsive. That walk to get his treat was the last time he walked. We rushed him to the vet, upon X-ray they found the splenic tumor. His gums were white and he was freezing. We were presented with the option of driving over an hour for emergency surgery without assurance he’d make it or euthanize him. He did not look like he would survive the drive so we opted to euthanize him. Plus it would be 4K min to so the transfusion and surgery and still might die. I am still trying to make sense of it all and my mind is whirling with how quickly we had to make the decision. We called as many local clinics as quickly as we could and no one was willing to perform the surgery. My heart aches wondering if he would’ve made it or if we did the humane thing.

Mark Novak
October 17, 2020

Thank you for this most helpful article. Our 13 ur old cairn terrier, Thomas, died yesterday of spontaneous hemoabdomen. One minute he was happily running through the woods on his walk, and the next minute he was knocked to the ground by spontaneous hemoabdomen. We rushed him to the vet, but it was too late. He died within 45 minutes. He didn’t appear to suffer.

October 12, 2020

We lost our 10 year old Maltese this past week.He grew a tumor on his Spleen this summer and we had it removed in late July, we was doing chemo and taking the herbal supplements. Was doing great, 2-3 walks a day, eating a lot and his vet appointment was great a week before two hours after we went on a walk his he lost both his back legs and had internal bleeding we put him down the next day.We were in shock and it's still extremely sad. When you read its extremely sudden and unpredictable they're 100% right. I don't wish this upon any dog

October 1, 2020

Just lost my ten year old GSD to this. Words cannot convey....

September 7, 2020

I just experienced this 2 days ago. I'm 'step'mum to our Newfoundland Indi. She was fine one minute and the next her legs gave out. I called her Dad told him she wasn't able to walk. I just recently broke my neck and back So I couldn't drive and she was 55kg more than 10kg heavier than myself. She started to deteriorate but her gums were still fairly pink. A few hours later I called the emergency pet ambulance and they arrived about 2hrs later and took her straight to emergency. They tested for everything - shaved her looking for bites or ticks. Nothing. Snake bite test. Rodenticide. Nothing. Then by 3 that afternoon she presented with irreversible haemorrhaging (bruises came up on her stomach) and I got a call to say she wouldn't make it. This killed me. I ubered to the emergency vet and they euthanized her in my arms. This broke me. I'm crying now. There we no other signs - she went to the toilet normally. Ate normally and was reacting fine. They thought it was ITP at first but the blood pooling bruising indicated cancer and rupture. $10000 for a blood transfusion but no guarantee after such trauma. I'm devastated and trying to find a reason and questioning everything. Asking questions about her food, what I could have done differently, whether she'd accidently eaten medication or anything thrown over the fence. I scoured that garden, and the house. I'd taken her to the vet at the beginning of the week and given antibiotics for a possible infection. Could they have spotted it then before this? Could I have? I can't be alone in the House without her.

Marion Boudreau
August 23, 2020

Hemangiosarcoma is an evil disease. I lost my sweet girl Vegas on Oct 9, 2018. One day she was fine, the next she was bleeding to death in her abdomen. She was only 10 years old but acted much younger. She was supposed to be a pit bull/lab mix but looked more like a Lab. She was so beautiful. Her only fault was she could not stand other dogs, so it was a really difficult production to get her to the vet. But otherwise she was just a big cuddle bug. She woke me up early in the morning of the 8th, shaking uncontrollably. I called the vet but they were closed but the vm gave me the number of another emergency vet. I was told to bring her in at 8 am. In the meantime I took her outside where she had a big poop and she seemed to feel better. We went back to bed for a while and got up about 7 am to get ready for the vet. She had to go out again and had another big bm. She seemed to feel fine then so I called the vet to let them know she was feeling better. They said to bring her in if anything changed. I wish I hadn't waited. She laid on the couch most of the day. That evening she started whimpering and crying. She got up and laid on the floor a while then went into the bedroom and laid down beside the bed. It was then I realized that something was very wrong because she was too weak to get onto the bed. I called the vet and was told to bring her right in. When we got there they noticed right off that her abdomen was distended and her gums were pale. They weighed her and she was only 70 lbs. She was previously about 90 lbs! They did an ultrasound and found an ugly grapefruit-sized mass on her spleen and the vet said her heart didn't sound right either and on the ultrasound it looked like there was fluid around her heart. They tested her blood and her clotting factor was extremely low. They told me that they could give her blood transfusions and possibly do a splenectomy but her chances of surviving the operation were very low and if she did survive she might not live for very long because this kind of tumor can spread to her other organs. The vet suspected that it already may have spread to her heart. The operation,drugs, transfusions, etc would cost over $6000. All the while Vegas was lying on a blanket, barely conscious. I was told that the kindest thing to do for her was to let her go. The vet left me with her for a while and I held her on my lap told her how much I loved her. I don't know if she could hear me or not. Then the vet came back and gave her the 2 needles, one to make her sleep and the second to stop her heart. It was the hardest thing I have ever done to leave her lifeless body there. It still seems like yesterday. All I have left are her ashes and memories. But the house is so empty now and I can't stop missing her. So much.

Jennas mom
August 7, 2020

My 10 yr old golden suddenly collapsed in June, we rushed her to the hospital and we are told it is a hemangiossrcoma on her heart. They did not biopsy it bc they say it is too risky to do on a heart tumor. We have done radiation and chemo and it is early August and she seems ok for now. Also giving her I’mYunity, which reportedly has good results and anti-tumor properties. She loves her daily walks and her appetite is really good. Doing everything we can. Love her so much!

July 14, 2020

I lost my Mimi on July 5th. It helps to frame it like a heart attack because it came out of nowhere. Luckily, due to the pandemic, I spent so much beautiful time with my girl. She lived life to the fullest until her last hours., I’m heartbroken.

Elizabeth Falloon
June 4, 2020

Somewhat comforting to know they’re others who experienced similar with my maxi

Steve C.
March 10, 2020

My 11.5 year old yellow lab, Daisy, was dx, via ultrasound, with an small spenic mass in November 2019 and the FNA on the mass was inconclusive for malignancy.  Nonetheless, we were going to schedule her for a splenectomy and biopsy after the Holidays were over, but she passed away unexpectedly on February 17, 2020- a two weeks before her surgery.  The mass must have ruptured during the night and she bled out within hours- we had absolutely no warning, since she was eating, drinking and playing all day with no issues to speak of.  Her passing was very, very sudden and my only advice is not to wait on the surgery, in order to avoid the sudden loss of a dear friend and family member.  My only hope was that she did not suffer at all, but I'm sure that she did, since she passed at home without any medical intervention to ease her pain.  Get the surgery and the piece of mind of knowing that you did all you could for your best friend.

Donna Brazill
January 10, 2020

Our little guy, Joey, age 14 had a splenectomy several months ago. Of course we were just sick that he might not make it through the surgery. He did! I cried all the way home and held my breath when the vet called and not the tech. He made it just fine and was letting them know he was ready to go home. He was running and carrying on like a puppy within a couple of days.  He is still doing wonderfully well. Eats like a little pig and back to being a cranky, older Lhasa. Much more appetite than he ever had before. It was a very difficult decision to make, but the thought of him possibly dying alone while we were at work due to a painful rupture was also an awful thought. The tumor was benign, but it was using 25% of his blood flow each day. Amazing how he had any energy at all prior to the surgery. We have an amazing vet who explained every detail of the procedure and that helped a lot. Now if we could just cure his congestive heart failure....

Hazel Sonnier
December 23, 2019

I took my Corgi to the vet due to her having some type of an episode the day before on the weekend. She seemed to have some type of seizure or slight stroke, couldn't stand, walk or hold head up for about 10 minutes and labored panting. She will be 13 on May3rd/2020. She's the queen at our home and has always been an inside furbaby. No summer heat or winter cold for her! Anyway, I had her there at opening and x-rays were taken of her belly, since the Dr could feel a large mass. She has Hemangiosarcoma. My life stood still for the next few minutes. She was given a week at the most and as few as days at best. My world came crashing down today. She was put on 4 medicines, 1 for swelling and 3 for pain. The mass is large and pushing her other organs upward and outward. We talked of the only 2 options and she thought taking her home was good maintaining her level of pain till mass ruptures and she dies. OMG... this is our baby and I can't believe she is dying. She has always been so healthy, no surgeries nothing! I took her afterward to her favorite place (Sonic) and got her a large double cheeseburger and she ate all! She loves riding on the golf-cart so we rode for 2 hours and visited the park and just hung out on a beautiful day. Tonight hubby and I are going on the cart to look at Christmas lights through our golfing community. Tomorrow rerun of today and every day afterward. Zoey's younger brother and sister won't leave her alone sniffy and loving on her. They sense or smell this dreaded disease or death. All 3 sleep next to one another and all 3 are inside furbabies....Boo/Golden & Ella/Australian Shephard, but Zoey/Corgi is the alpha. A 110 pound and 75 pound knows she's the boss and was here 1st! lol  Prayers Appreciated!

Molly Jari
January 9, 2017

Thank you for this article and all the information you share.  Also to everyone who writes in with their experience.  I am constantly looking for any new information on hemangiomasarcoma. My dog was dx with a 10 cm splenic mass 16 months ago - assumed HSA. She was almost 12 at the time and like Sara (April 2016 post) chose not to try the surgery for splenectomy.  My dog is doing amazingly well. below is a link to our blog if you're interested in how we are working with diet, herbals, exercise and homeopathy to support her health.  I realize every case is different and do not want to imply that we have found a cure, we have not, but there may be some support here if your dog is still living with hemangioma - sarcoma or any other cancer.

November 20, 2016

I came across this article when doing a search for why a dog with hemoabdomen would code under anesthesia. I am a certified vet tech, having graduated from Tech school in 2007. I've run anesthesia thousands of times and have never had one code during. Until this weekend. It was an 11y, MN, Golden. Everything was going good until it wasn't. He presented recumbent, and dx with hemoabdomen. Fluids were bolused, pre-med given, intubated, scrubbed, then he went agonal. The cause of hemorrhage could not be found, but mets were everywhere. I understand that he was level 5 surgical risk, but it stills troubles me that this happened.

April 17, 2016

My dog was diagnosed with a splenic mass in November 2014. I looked into the options and decided to take him home with no medical interventions.  He is still here. Now I wish I had done the surgery as it must be benign, but a year and a half later I just can put Him through this surgery at 12. A very difficult situation.

April 22, 2015

What a great spot on article- so well written. I've come to expect nothing less of Dr Tony Johnson. Incredibly intelligent educator- I "stalk" him on  VIN. His sense of humor goes a long way too. Thanks for a fantastic article on a horrid disease.

Renee M 
April 21, 2015

I've dealt with a hemangiosarcoma of the heart. . only reason we caught it was he had pneumonia. . .a horrid horrid freaking disease

Linda Baitz 
April 21, 2015

I lost 3 furry daughters within 14 months, Jan 2014-March 2015, all over 15 yrs old, the last, a Siberian huskie on her 16th b-day.  When it was our shitzu's time we took her to her dr. and he told us he thought that we would have been back within a month of her tumor removal,7 months prior,  because it was such a nasty looking cancer. I am glad he didn't tell us because we wouldn't have not let her live like nothing was wrong.  She went about her day being the boss of all of us and being her loveable bratty self.

Mike Fuller 
April 21, 2015

We just had to put down Kalie a 13 yr old love of our lives. My better-half Marti is a vet and retired, she gave me the bad news just as the vet who was treating her came in with the same news. We had 13 yrs with a wonderful friend. RIP my love

Connie Moore 
April 21, 2015

My dog Wiggles a 12-year-old male Pekingese was unfortunate to have a splenic mass that weighed 1.3 pounds taken from his body that turned out to be his histiosarcoma.  He is now on chemotherapy taking lomustine and has been doing well although lately we've had about swear he doesn't like to eat and he got a little sick a week ago but is slowly recovering I'm fortunate enough to work in a veterinary emergency clinic where I can provide chemotherapy for my dog at a discounted rate but I totally understand where that doctors coming from he is our baby and we will keep him here with us until he tells us it's time for him to go and at that point I hope to bring him home and do the same thing make him leave his final days like there's no tomorrow we love him so much.


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