Meet Our Cardiac Surgeons
Get to know the surgeons trusted by families throughout Northern Kentucky and Greater Cincinnati – experienced, approachable and ready to answer your questions.
Regional Leaders. Local Roots. World-Class Expertise.
Every surgeon on our team brings more than skill to the operating room – they bring a story, a sense of purpose and a commitment to making a difference for every patient.
Some found their calling through family experiences with heart disease. Others were inspired by mentors, or by the challenge of solving complex problems with their hands and minds. What unites them is a drive to help people get back to the moments and milestones that matter most.
You’ll see this purpose reflected in every conversation, every decision and every step of your care. As you read their bios, you’ll discover how each surgeon’s journey shapes the way they approach medicine – and how their dedication becomes part of your story.
Mario Castillo-Sang, MD
Born in Panama, Dr. Castillo-Sang grew up tagging along with his veterinarian father, learning the value of hands-on care and curiosity. He’s a pioneer in totally endoscopic minimally invasive cardiac surgery in the U.S., performing nearly all his procedures through a single 2.5cm incision. He has advanced the management of complex heart problems such as mitral calcification using totally endoscopic techniques.
Dr. Castillo-Sang plans every surgery like a chess match – anticipating every move, every “what if.” He’s known for his meticulous technique, global teaching contributions and commitment to patient education – ensuring his patients have a clear understanding of what’s happening with their heart and how he plans to repair it.
“It’s fun to do challenging things with your hands and your mind – especially when the end result is helping a person.”
Schedule a Consultation with Dr. Castillo-Sang
George Christensen, DO
Dr. Christensen’s journey started with his father’s heart attack, teaching him the importance of family, teamwork and resilience. He’s known for his steady presence, kind demeanor and for treating every patient as a whole person, not just a diagnosis.
He’s a dad, a former hockey hopeful and a believer in the power of collaboration – whether it’s reviewing care plans with colleagues or sharing a moment with a patient’s family. Patients often describe him as genuine, reassuring and deeply invested in their recovery.
“For me, heart surgery is about more than fixing what’s wrong – it’s about helping people get back to the lives they thought they’d lost and seeing them smile again.”
Schedule a Consultation with Dr. Christensen
Michael “Mickey” Ising, MD
Dr. Ising grew up in Elizabethtown, Kentucky, playing soccer and dreaming big. He started his career as an engineer, fascinated by the mechanics of artificial hearts before deciding he’d rather help real people than design devices.
He’s known for his humbleness, optimism and for making patients feel seen – whether he’s talking about football, sweet potato casserole, or the best hidden gems in Northern Kentucky. He believes that healing begins with connection – because for Dr. Ising, surgery isn’t just clinical, it’s deeply personal.
“I literally hold my patients’ hearts in my hands – that experience isn’t lost on me. Their trust means everything.”
Schedule a Consultation with Dr. Ising
Michael Kasten, MD
Dr. Kasten is a Lexington native, a car enthusiast and a self-described “fancy plumber” who loves fixing things – whether it’s a classic car or complex heart conditions.
He’s known for his boundless energy, his knack for analogies and his ability to make even the most complex procedures feel understandable and manageable for patients. Dr. Kasten has extensive experience in surgically treating atrial fibrillation using robot-assisted techniques.
“Every patient deserves to feel heard, supported and confident in their care – that’s the standard I hold myself to.”
Schedule a Consultation with Dr. Kasten
Juan Penaranda-Canal, MD
Dr. Penaranda-Canal grew up in Colombia, surrounded by creativity and a big family. He chose medicine to connect with people and make a difference. He’s passionate about bringing new technologies and minimally invasive techniques to Northern Kentucky.
He’s known for his curiosity and for making patients feel comfortable, informed and truly cared for. His approach blends technical precision with genuine empathy. Patients often describe him as exceptional in both skill and bedside manner.
“Heart surgery has the power to restore not just health, but hope – the most rewarding thing is seeing patients come back after surgery, feeling renewed and full of energy.”
Schedule a Consultation with Dr. Penaranda-Canal
Facing Heart Surgery? Here’s What You Should Know
Heart surgery isn’t something you go through every day. You might be feeling a mix of worry, hope and questions right now. That’s normal.
Our team is here to listen, explain and support you – whether you want to know every detail or just need someone to say, “I’m right here.” If you’re unsure about what comes next, reach out. We’ll help you find your footing.
Your Cardiac Surgery Care Navigator
Facing heart surgery can feel overwhelming. You don’t have to figure this out alone. Your Cardiac Surgery Care Navigator is here to answer questions; coordinate appointments and make sure you always know what’s next.
Connect with a Cardiac Surgery Care Navigator today, call (859) 301-9010.
Frequently Asked Questions
Ready to Talk?
Call (859) 301-9010 to speak with a Cardiac Surgery Care Navigator or request a heart surgery consultation online:
