Meet Dr. Ash

The view from the end of the road

Im Ashvin Vijayakumar (Dr. Ash). I spent the first years of my career in the hospital, working the ICU, the ER, and the general medical wards, and thats where I learned what the end stage of chronic disease looks like up close: the heart attacks, the strokes, and the metabolic crashes that arrive after decades of quiet buildup. What stayed with me was less the crisis itself and more the trail of small signals that showed up 20 and 30 years earlier, back when someone could still change course.

That instinct doesnt come from a textbook. It comes from standing in the room at the worst moment, then doing the math on what could have caught it 20 years sooner, and learning to read those signals backward.

Why I built this practice

After residency and a fellowship in value-based care leadership, I spent years building that kind of care inside startups and then a Fortune 5 company, including a run at Oak Street Health that I left as a board-elected medical director and partner. I believed in the mission. But the same pattern I saw in the hospital kept turning up in those systems: smart, driven people getting failed by care built for quick fixes and 12-minute visits.

It kept me circling one question, the one that drives this whole practice: why some people stay sharp and strong into their 90s while others start to slip in their 60s. The pattern I kept seeing was engagement. Someone was paying attention early and adjusting the plan while there was still room to adjust, and the people who struggled were usually running on wait-and-see.

Almost none of the complications I managed in the ICU were inevitable. Most were the last chapter of a story that started 20 or 30 years earlier, when a fasting insulin began climbing or an ApoB number got waved off as fine.

That is the lens I bring to every patient's story. When people send me records from prior cardiologists and primary care doctors, the notes often read normal, and that answer fit the question those doctors had time to ask. I ask a different one: where your trajectory is pointed for the next 20 years, and whether we like the direction.

Fishtown Medicine exists to work in those middle chapters, your 30s, 40s, and 50s, when the moves are still simple and the upside is biggest. Thats the whole reason I built it as primary care with time: long visits, direct access, and one physician holding your full picture.

How I practice

Three principles, woven into every visit.

GER·O·SPAN, our framework

I built GER·O·SPAN as the working model for healthspan medicine. GERO covers the things that shape you (Genetics, Environment, Relationships, and Our work as your physician at the fulcrum). SPAN covers the levers you control (Sleep, Physical Activity, Nutrition). The interesting work is at the fulcrum, where data becomes a coherent picture and the picture becomes the next right action.

You run your biology; I translate it

The old model, where the doctor gives orders and the patient complies, is over. You are the operator of your biology, and my job is to translate the data, show you the trade-offs, and help you choose. I explain the reasoning, then hand you the wheel. Your wine and your late nights are part of the data we work with, and we read the numbers together, HRV, sleep, ApoB, fasting insulin, liver enzymes, to decide what is worth changing for the life you want.

Complications-informed care

Because Ive seen the late-stage version of nearly every chronic disease, I catch the early signals most visits miss: the insulin edging up years before a diabetes diagnosis, the ApoB climbing before a calcium scan would ever catch the plaque, and the low-grade fatigue and drifting HRV that show up before a full burnout. I push hard on prevention because Ive watched, up close, what waiting costs.

Clinical Background (LinkedIn)

Training

• MD: American University of Antigua College of Medicine
• Residency: Internal Medicine (AtlantiCare Regional Medical Center)
• Fellowship: Value-Based Care Delivery Leadership (Mount Sinai Icahn School of Medicine)
• Board Certification: Internal Medicine (ABIM), certified since 2014

Experience

• Former Partner: Oak Street Health
• Former Medical Director: CVS Healthspire
• Focus: Preventive cardiology, metabolic optimization, longevity medicine

The Practice Model

The Fishtown Medicine practice model combines the rigor of internal medicine with the precision of preventive cardiology. In practice, that means:

• Deep Diagnostics: We go beyond the standard panel and look at fasting insulin, advanced lipids, and micronutrients to find what "normal" labs miss.
• Continuity that compounds: We get to know you and track your trends over years, so prevention rests on your own baseline instead of a population average pulled from a 15-minute visit.
• Evidence over dogma: Guidelines are a starting point, and when the evidence supports a better approach for your situation, we take it.
• Context Matters: A lab value only makes sense in the context of your life. We connect the dots between your biology and your biography.

Who this practice is for

The shared trait across our members is that the standard system has not been good to them. From there it splits into a few clear archetypes:

• The complex chronic patient. Perimenopause symptoms, functional GI, unexplained fatigue with "normal" labs, autoimmune work-ups that never connected. You have seen specialists who didnt talk to each other. You want one doctor who sits with the whole chart.
• The preventive optimizer. You read Attia and Huberman. You want ApoB, Lp(a), fasting insulin, VO2 max guidance, hormone optimization. You are not interested in waiting until something is broken.
• The patient burned by primary care. You were rushed through 12-minute visits. You want a quarterback. You want to be able to text and get a straight answer.
• The acute single-issue patient. A rash, a travel-vaccine question, a second opinion on a lab. You dont want to sign a year-long contract, you want one good visit.
• The hospitality and service-industry member. Restaurant, bar, salon, school, hospital. You cant miss a shift for a sinus infection. You text us at 11 pm and we read it.
• The busy parent. You are managing a household, and your own health is usually last on the list. We handle the small stuff by text so you dont have to take a half day off.

Most care happens over text and video. When you need an in-person exam, I come to you at home, in 19125 or anywhere across the Greater Philadelphia metro.

Let's talk

If you are tired of being told you are fine when you do not feel fine, or you just want a doctor who has the time to think it through with you, let's talk. A membership here is HSA and FSA eligible, so this is tax-free longevity, care you can pay for with pre-tax dollars.

Tell Dr. Ash what's going on

Credentials

Board Certification: American Board of Internal Medicine (ABIM)
NPI: 1659782464
Medical Licenses: Active and in good standing in AL, AZ, CO, CT, DC, DE, FL, GA, GU, HI, IA, ID, IL, IN, KS, KY, LA, ME, MD, MN, MO, MS, MT, NE, NH, NJ, NV, NY, ND, OH, OK, PA, SD, TN, TX, UT, VT, WA, WI, WV, WY
Memberships: American College of Physicians (ACP), American Society for Preventive Medicine (ASPM)

Scientific References

1. Attia P. Outlive: The Science and Art of Longevity. Harmony Books; 2023.
2. Kohane IS. The Twin Imperatives of Personalized Medicine. N Engl J Med. 2017;377(8):e8.
3. American Academy of Family Physicians. Direct Primary Care: A New Way to Pay for Health Care. Fam Pract Manag. 2018;25(1):16-20.

Fishtown Medicine provides virtual-first and home-visit based internal medicine throughout Greater Philadelphia. We focus on low-friction, high-relationship care.